Hammett equation - Knowledge

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group will increase the rate due to stabilization of the extra charge which is put on the carbon in the transition state. On the other hand, if the nucleophile is not charged (e.g. triphenylphosphine), electron withdrawing group is going to slow down the reaction by decreasing the electron density in the anti bonding orbital of leaving group in the transition state.

1943:σ- is designated in the case where negative charge buildup in the transition state occurs, and the rate of the reaction is consequently accelerated by electron withdrawing groups (EWG). The EWG withdraws electron density by resonance and effectively stabilizes the negative charge that is generated. The corresponding plot will show a positive rho value. 1936: 1911: 1950:

the effect of the substituent, X, of the non-leaving group can in fact accelerate the rate of the nucleophilic addition reaction when X is an EWG. This is attributed to the resonance contribution of the EWG to withdraw electron density thereby increasing the susceptibility for nucleophilic attack on

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Another deviation from the regular Hammett equation is explained by the charge of nucleophile. Despite nonlinearity in benzylic SN2 reactions, electron withdrawing groups could either accelerate or retard the reaction. If the nucleophile is negatively charged (e.g. cyanide) the electron withdrawing

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Roberts and Moreland studied the reactivities of 4-substituted bicyclooctane-1-carboxylic acids and esters. In such a molecule, transmission of electrical effects of substituents through the ring by resonance is not possible. Hence, this hints on the role of the π-electrons in the transmission of

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Reactivity data indicate that the effects of substituent groups in determining the reactivities of substituted benzoic and bicyclo-octane-1-carboxylic acids are comparable. This implies that the aromatic π-electrons do not play a dominant role in the transmission of electrical effects of dipolar

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is positive, causing partial cancellation. The data also show that for these substituents, the meta effect is much larger than the para effect, due to the fact that the mesomeric effect is greatly reduced in a meta substituent. With meta substituents a carbon atom bearing the negative charge is

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value. In such a case, it is likely that the mechanism of the reaction changes upon adding a different substituent. Other deviations from linearity may be due to a change in the position of the transition state. In such a situation, certain substituents may cause the transition state to appear

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is related to the charge during the rate determining step, mechanisms can be devised based on this information. If the mechanism for the reaction of an aromatic compound is thought to occur through one of two mechanisms, the compound can be modified with substituents with different

1253:. Note that the scaling factor is negative, since an electron-donating group speeds up the reaction. For a reaction whose Hammett plot is being constructed, these alternative Hammett constants may need to be tested to see if a better linearity could be obtained. 1356:, describes the susceptibility of the reaction to substituents, compared to the ionization of benzoic acid. It is equivalent to the slope of the Hammett plot. Information on the reaction and the associated mechanism can be obtained based on the value obtained for 1927:

of the reaction. For the reason of the former case, new sigma constants have been introduced to accommodate the deviation from linearity otherwise seen resulting from the effect of the substituent. σ+ takes into account positive charge buildup occurring in the

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The opening line in his 1935 publication reads: "The idea that there is some sort of relationship between the rate of a reaction and the equilibrium constant is one of the most persistently held and at the same time most emphatically denied concepts in chemical

1402:. If one of these mechanisms involves the formation of charge, this can be verified based on the ρ value. Conversely, if the Hammett plot shows that no charge is developed, i.e. a zero slope, the mechanism involving the building of charge can be discarded. 1918:

The plot of the Hammett equation is typically seen as being linear, with either a positive or negative slope correlating to the value of rho. However, nonlinearity emerges in the Hammett plot when a substituent affects the rate of reaction or changes the

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A change in the mechanism of a reaction also results in nonlinearity in the Hammett plot. Typically, the model used for measuring the changes in rate in this instance is that of the SN2 reaction. However, it has been observed that in some cases of an

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that an EWG does not accelerate the reaction as would be expected and that the rate varies with the substituent. In fact, the sign of the charge and degree to which it develops will be affected by the substituent in the case of the benzylic system.

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Likewise, the carbonyl carbon of a benzoic acid is at a nodal position and unable to serve as a sink for +M groups (in contrast to a carbocation at the benzylic position). Thus for reactions involving carbocations at the α-position, the

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the images in the section are too loosely tied to the text, e.g., there is no mention of sulfinate ester or imine hydrolysis, though this is what the schemes present, and there are no sources indicated for the schemes, violating either

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remain almost constant through the series. The linear relationship fit well in the Hammett Equation. For the 4-substituted bicyclooctane-1-carboxylic acid derivatives, the substituent and reaction constants are designated σ’ and ρ’.

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Stein, Allan R.; Tencer, Michal; Moffatt, Elizabeth A.; Dawe, Robert; Sweet, James (1980). "Nonlinearity of Hammett .sigma..rho. correlations for benzylic systems: activation parameters and their mechanistic implications".

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The latter two influences are often treated together as a composite effect, but are treated here separately. Westheimer demonstrated that the electrical effects of π-substituted dipolar groups on the acidities of

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Reactivity of 4-substituted bicyclooctane-1-carboxylic acids and esters were measured in 3 different processes, each of which had been previously used with the benzoic acid derivatives. A plot of log(k) against

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Roberto Todeschini, Viviana Consonni, Raimund Mannhold, Hugo Kubinyi & Hendrik Timmerman, 2008, "Entry: Electronic substituent constants (Hammet substituent constants, σ electronic constants)," in

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The effect of the substituent may change the rate-determining step (rds) in the mechanism of the reaction. A certain electronic effect may accelerate a certain step so that it is no longer the rds.

1470:. Westheimer's treatment worked well except for those acids with substituents that have unshared electron pairs such as –OH and –OCH3, as these substituents interact strongly with the benzene ring. 1932:

of the reaction. Therefore, an electron donating group (EDG) will accelerate the rate of the reaction by resonance stabilization and will give the following sigma plot with a negative rho value.

345: 126: 1494:) showed a linear relationship. Such linear relationships correspond to linear free energy relationships, which strongly imply that the effect of the substituents are exerted through changes of 3047:

Linderberg, B.; Svensson, S.; Malmquist, P.A.; Basilier, E.; Gelius, U.; Siegbahn, K. (1976). "Correlation of ESCA shifts and Hammett substituent constants in substituted benzene derivatives".

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Because the carbonyl group is unable to serve a source of electrons for -M groups (in contrast to lone pair donors like OH), for reactions involving phenol and aniline starting materials, the

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Francis A. Carey & Richard J. Sundberg, 2006, "Title Advanced Organic Chemistry: Part A: Structure and Mechanisms," 4th Edn., New York, NY, US: Springer Science & Business Media,

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Takahata Y.; Chong D.P. (2005). "Estimation of Hammett sigma constants of substituted benzenes through accurate density-functional calculation of core-electron binding energy shifts".

1832:− σ’). This is expected as electron resonance effects are felt more strongly at the p-positions. The (σ – σ’) values can be taken as a reasonable measurement of the resonance effects. 817:

of the carboxylic acid (depicted on the left of the equation) has increased. These substituents stabilize the negative charge on the carboxylate oxygen atom by an electron-withdrawing

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Young, P. R.; Jencks, W. P. (1979). "Separation of polar and resonance substituent effects in the reactions of acetophenones with bisulfite and of benzyl halides with nucleophiles".

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values for electron-withdrawing groups will appear too small. For reactions where resonance effects are expected to have a major impact, a modified parameter, and a modified set of

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the carbonyl carbon. A change in rate occurs when X is EDG, as is evidenced when comparing the rates between X = Me and X = OMe, and nonlinearity is observed in the Hammett plot.

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Of course, when the sign for the reaction constant is negative (next section), only substituents with a likewise negative substituent constant will increase equilibrium constants.

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Keenan, Sheue L.; Peterson, Karl P.; Peterson, Kelly; Jacobson, Kyle (2008). "Determination of Hammett Equation Rho Constant for the Hydrolysis of p-Nitrophenyl Benzoate Esters".

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with positive charge on the X substituent, releasing electrons and thus destabilizing the Y substituent. This destabilizing effect is not possible when X has a meta orientation.

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Bols, Mikael; Liang, Xifu; Jensen, Henrik H. (2002). "Equatorial contra axial polar substituents. The relation of a chemical reaction to stereochemical substituent constants".

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groups to the ionizable carboxyl group Difference between ρ and ρ’ for the reactions of the acids with diphenylazomethane is probably due to an inverse relation to the solvent

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to see how they correlate with Hammett σ-constants. Linear plots were obtained when the calculated CEBE shifts at the ortho, meta and para carbon were plotted against Hammett

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Roberts J.D.; Moreland Jr. W.T. (1953). "Electrical Effects of Substituent Groups in Saturated Systems. Reactivities of 4-Substituted Bicyclo octane-1-carboxylic acids".

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Michael B. Smith & Jerry March, 2007, "March's Advanced Organic Chemistry: Reactions, Mechanisms, and Structure," 6th Ed., New York, NY, US: Wiley & Sons,

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Reaction constants are known for many other reactions and equilibria. Here is a selection of those provided by Hammett himself (with their values in parentheses):

238: 2178:, etc. The fluorine atom is para with respect to the substituent Z in the benzene ring. The image on the right shows four distinguished ring carbon atoms, C1( 2202:-Z molecule. The carbon with Z is defined as C1(ipso) and fluorinated carbon as C4(para). This definition is followed even for Z = H. The left-hand side of ( 801:

The σ values displayed in the Table above reveal certain substituent effects. With ρ = 1, the group of substituents with increasing positive values—notably

882:, can even have opposite signs for the substituent constant as a result of opposing inductive and mesomeric effect. Only alkyl and aryl substituents like 2008:

type reaction, in which case the resulting Hammett plot will indicate a rate acceleration due to an EDG, thus elucidating the mechanism of the reaction.

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Y. Yukawa & Y. Tsuno, 1959, "Resonance Effect in Hammett Relationship. II. Sigma Constants in Electrophilic Reactions and their Intercorrelation,"

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are the Hammett reaction constants for the reaction of the neutral molecule and core ionized molecule, respectively. ΔCEBEs of ring carbons in p-F-C

2491: 2388: 716:, a series of equilibrium constants (K) are now determined based on the same process, but now with variation of the para substituent—for instance, 1367:, the reaction is more sensitive to substituents than benzoic acid and negative charge is built during the reaction (or positive charge is lost). 2412: 2436: 2698:

Table values are this original 1937 publication, and differ from values appearing in subsequent publications. For more standard values, see:

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values and kinetic measurements taken. Once these measurements have been made, a Hammett plot can be constructed to determine the value of

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Kirkwood J.G.; Westheimer F.H. (1938). "The electrostatic influence of substituents on the dissociation constants of organic acids. I ".

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Westheimer F.H. (1939). "The Electrostatic effect of substituents on the dissociation constants of organic acids. IV. Aromatic acids".

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to each other with just two parameters: a substituent constant and a reaction constant. This equation was developed and published by

2985: 2923: 1435:: electrical influence of a group which is transmitted primarily by polarization of the bonding electrons from one atom to the next 57:

The basic idea is that for any two reactions with two aromatic reactants only differing in the type of substituent, the change in

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can be quantitatively correlated, by assuming only direct electrostatic action of the substituent on the ionizable proton of the

2424: 2400: 1604: 1284: 3291: 1373:, the reaction is less sensitive to substituents than benzoic acid and negative charge is built (or positive charge is lost). 1804:

are more positive than σ’. (The superscript, c, in table denotes data from Hammett, 1940.) For ortho-para directing groups (

2465: 2208:) is called CEBE shift or ΔCEBE, and is defined as the difference between the CEBE of the fluorinated carbon atom in p-F-C 485: 301: 82: 3306: 3257: 2378:

Hence the approximate agreement in numerical value and in sign between the CEBE shifts and their corresponding Hammett

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for which the substituent constant is arbitrarily set to 0 and the reaction constant is set to 1: the deprotonation of

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C. Hansch; A. Leo; R. W. Taft (1991). "A survey of Hammett substituent constants and resonance and field parameters".

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values for electron-donating groups will appear insufficiently negative. Based on similar considerations, a set of

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Hammett, Louis P. (1937). "The Effect of Structure upon the Reactions of Organic Compounds. Benzene Derivatives".

2081: 832:, for which the substituent effect is still positive but much more modest. The reason for this is that while the 3239: 3221: 3164: 3150: 3136: 2744: 2038: 1947: 1246:{\displaystyle \sigma _{p}^{+}=-{\frac {1}{4.54}}\log _{10}\left({\frac {k_{{\ce {X}}}}{k_{{\ce {H}}}}}\right)} 942: 1975: 1405:

Hammett plots may not always be perfectly linear. For instance, a curve may show a sudden change in slope, or

1096:{\displaystyle \sigma _{p}^{-}={\frac {1}{2.11}}\log _{10}\left({\frac {K_{{\ce {X}}}}{K_{{\ce {H}}}}}\right)} 2881:

Um, Ik-Hwan; Lee, Ji-Youn; Kim, Han-Tae; Bae, Sun-Kun (2004). "Curved Hammett plot in alkaline hydrolysis of

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With knowledge of substituent constants it is now possible to obtain reaction constants for a wide range of

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combined with that of many substituted ethyl benzoates ultimately result in a reaction constant of +2.498.

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for "non-anomalous" substituents, so as to maintain comparable ρ values: for ArOH ⇄ ArO + H, we define

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Frank Westheimer, 1997, "Louis Plack Hammett, 1894—1987: A Biographical Memoir," pp. 136–149, in

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Core-electron binding energy (CEBE) shifts correlate linearly with the Hammett substituent constants (

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is the reference reaction rate of the unsubstituted reactant, and k that of a substituted reactant.

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for a given reaction rate with many differently substituted reactants will give a straight line.

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Hart, H.; Sedor, Edward A. (1967). "Mechanism of cyclodehydration of 2-phenyltriarylcarbinols".

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may contain an excessive amount of intricate detail that may interest only a particular audience

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constants may give a better fit. This parameter is defined using the ionization constants of

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Louis P. Hammett (1935). "Some relations between Reaction Rates and Equilibrium Constants".

3094: 3057: 2885:-aryl thionobenzoates: Change in rate-determining step versus ground-state stabilization". 2795: 2570: 2045:. An equation that addresses stereochemistry in aliphatic systems has also been developed. 1483: 1389:

These relations can be exploited to elucidate the mechanism of a reaction. As the value of

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constants give better fit for reactions involving electron-donating groups at the

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which is transmitted primarily to the reactive group through space (including

3300: 3013: 2957: 2539:, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) " 2034: 1297: 1274: 795: 755: 292: 32: 2548: 2080:

any relevant information, and removing excessive detail that may be against

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which depends only on the type of reaction but not on the substituent used.

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in 1937 as a follow-up to qualitative observations in his 1935 publication.

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Other equations now exist that refine the original Hammett equation: the

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The starting point for the collection of the substituent constants is a

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position and the formation of a carbocation at the benzylic site. The

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L.P.Hammett, 1940, "Chapter III," "Chapter IV," and "Chapter VII," in

2807: 2582: 1273:(R=R'=H) in a water/ethanol mixture at 30 °C. Measurement of the 786:

substituents. Repeating the process with meta-substituents afford the

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substituted phenols, via a scaling factor to match up the values of

916: 3258:"The beginnings of physical organic chemistry in the United States" 2112: 810: 771: 763: 2216:-Z and that of the fluorinated carbon in the reference molecule FC 2000:

For example, the substituent may determine the mechanism to be an

2124: 2013: 1503: 1447: 1385:, the reaction builds positive charge (or loses negative charge). 1379:, no sensitivity to substituents, and no charge is built or lost. 1345: 1315: 1304: 875: 860: 829: 814: 767: 747: 295:

k of a series of reactions with substituted benzene derivatives:

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Direct electrostatic (field) effect: electrical influence of a

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John Shorter, 2000, "The prehistory of the Hammett equation,"

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further away from the carboxylic acid group (structure 2b).

809:—cause the equilibrium constant to increase compared to the 3127:

Thomas H. Lowry & Kathleen Schueller Richardson, 1987,

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and a Hammett substituent constant at the para position,

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which depends only on the specific substituent R and the

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1 reaction of cumyl chlorides in 90% acetone/water: for

734:. These values, combined in the Hammett equation with K 2953: 2739:

pp. TBD, Sausalito, CA, US: University Science Books,

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Plot of calculated CEBE shift (eV) against sigma-meta

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Plot of calculated CEBE shift (eV) against sigma-para

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4-substituted bicyclo-2.2.2.-octane-1-carboxylic acid

1162: 1015: 428: 388: 356: 304: 249: 224: 193: 171: 140: 85: 340:{\displaystyle \log {\frac {k}{k_{0}}}=\sigma \rho } 121:{\displaystyle \log {\frac {K}{K_{0}}}=\sigma \rho } 3234:New York, NY, US: Springer Science & Business, 3232:

Correlation Analysis in Chemistry: Recent Advances,

3290:Washington, DC, US: National Academies Press, see 2442:Plot of calculated CEBE shift (eV) against sigma-o 1245: 1095: 454: 414: 371: 339: 264: 232: 199: 177: 155: 120: 3298: 2664:Carey, Francis A.; Sundberg, Richard J. (1983). 2635: 1413: 1352:The reaction constant, or sensitivity constant, 3010: 2756: 3131:3rd Edn., New York, NY, US: Harper & Row, 2667:Advanced Organic Chemistry Part A, 2nd edition 1410:earlier (or later) in the reaction mechanism. 1321:the acid catalyzed bromination of substituted 3214:Methods and Principles in Medicinal Chemistry 2949: 2947: 2945: 2920: 2663: 2631: 2629: 2627: 2598: 2596: 2594: 2592: 1615:Please help adding a more precise page range. 1450:, if any) according to the laws of classical 870:Scheme 3. Hammett Inductive Mesomeric Effects 65:. This notion does not follow from elemental 16:Free-energy relationship in organic chemistry 2492:Quantitative structure–activity relationship 892: 3189:Correlation Analysis of Organic Reactivity, 2982: 2880: 1288:Scheme 2. Hydrolysis of benzoic acid esters 945:. Unsourced material may be challenged and 73:and was introduced by Hammett intuitively. 3129:Mechanism and Theory in Organic Chemistry, 3086:International Journal of Quantum Chemistry 2942: 2624: 2589: 482:(R and R' both H) in water at 25 °C. 3202: 2454:Table of CEBE shifts (eV) and sigma-ortho 2158:Consider para-disubstituted benzene p-F-C 2100:Learn how and when to remove this message 1898:Learn how and when to remove this message 1631:Learn how and when to remove this message 1583: 1510: 965:Learn how and when to remove this message 886:are electron-releasing in both respects. 3184:2nd Edn., New York, NY, US: McGraw-Hill. 2657: 2430:Table of CEBE shifts (eV) and sigma-meta 2406:Table of CEBE shifts (eV) and sigma-para 2024: 465: 3255: 2602: 2524: 489:Scheme 1. Dissociation of benzoic acids 455:{\displaystyle \log {\frac {k}{k_{0}}}} 415:{\displaystyle \log {\frac {K}{K_{0}}}} 3299: 3196:Correlation Analysis of Chemical Data, 2049:Estimation of Hammett sigma constants 848:, where, in a para substituted arene 828:The next set of substituents are the 738:and remembering that ρ = 1, give the 2289: 2226: 2129: 2052: 1839: 1824:– σ’) is greater than that between σ 1587: 943:adding citations to reliable sources 910: 2541:Hammett equation (Hammett relation) 1601:This section cites its sources but 1546:Alkaline hydrolysis of ethyl esters 1422:electrical influences predominate: 13: 3210:Handbook of Molecular Descriptors, 3116: 2737:Modern Physical Organic Chemistry, 2735:E.V. Anslyn & D.A. Dougherty, 2536:Compendium of Chemical Terminology 2111: 1991: 1974: 1934: 1909: 1472: 1283: 865: 790:. This treatment does not include 484: 14: 3323: 1794:electron withdrawing group or EWG 1314:of substituted benzoic esters in 1265:. The archetypal reaction is the 272:when R is a hydrogen atom to the 61:is proportional to the change in 2852:, New York, NY, US: McGraw-Hill. 2447: 2435: 2423: 2411: 2399: 2387: 2057: 2012: 1967: 1955: 1844: 1592: 1348:-water at 69.8 °C (-1.875). 915: 3076: 3040: 3004: 2976: 2914: 2874: 2855: 2842: 2814: 2778: 1979:change in rate determining step 1835: 1560:Acids with diphenyldiazomethane 1300:ester in ethanol/water (+1.267) 422:for a given equilibrium versus 2750: 2729: 2692: 2553: 2504: 1948:nucleophilic acyl substitution 1806:electron donating group or EDG 1340:the hydrolysis of substituted 1303:the ionization of substituted 1296:the hydrolysis of substituted 1: 2518: 1414:Dominating electronic effects 712:Having obtained a value for K 39:for many reactions involving 3070:10.1016/0009-2614(76)85053-1 2466:Bell–Evans–Polanyi principle 2269:is a product of a parameter 2082:Knowledge's inclusion policy 1482:substituent effects through 1256: 821:(-I) and also by a negative 813:reference, meaning that the 291:The equation also holds for 7: 3182:Physical Organic Chemistry, 2459: 2317: 2283: 2265: 2263:The right-hand side of Eq. 2253: 2204: 2148: 1864:. The specific problem is: 1792:For meta-directing groups ( 1418:3 kinds of ground state or 844:This effect is depicted in 502:substituted benzene rings. 10: 3328: 3307:Physical organic chemistry 3249: 3121: 2850:Physical Organic Chemistry 2039:Grunwald–Winstein equation 1816:. The difference between σ 1808:), σ’ more positive than σ 788:meta substituent constants 740:para substituent constants 3256:Roberts, John D. (1996). 3198:New York, NY, US: Plenum. 3174: 2347:density functional theory 874:Other substituents, like 59:free energy of activation 3293:, accessed 22 June 2015. 3245:, accessed 22 June 2015. 3227:, accessed 22 June 2015. 3170:, accessed 19 June 2015. 3156:, accessed 19 June 2015. 3142:, accessed 20 June 2015. 2871:, accessed 22 June 2015. 2497: 2476:Free-energy relationship 2367:constants respectively. 2345:-Z were calculated with 2230:ΔCEBE ≡ CEBE(C4 in p-F-C 794:, which would introduce 742:compiled in table 1 for 29:free-energy relationship 2549:10.1351/goldbook.H02732 836:is still negative, the 494:Substituent constants: 480:benzene carboxylic acid 372:{\displaystyle {k}_{0}} 265:{\displaystyle {K}_{0}} 178:{\displaystyle \sigma } 156:{\displaystyle {K}_{0}} 76:The basic equation is: 3203:Surveys of descriptors 2238:-Z) – CEBE(C4 in p-F-C 2116: 1997: 1980: 1940: 1915: 1584:Comparison of σ and σ’ 1511:Comparison of ρ and ρ’ 1478: 1289: 1247: 1097: 871: 490: 456: 416: 373: 341: 283:reaction rate constant 266: 234: 209:Reaction rate constant 201: 185:= Substituent constant 179: 157: 122: 3288:Biographical Memoirs, 2863:Bull. Chem. Soc. Jpn. 2374:value calculated ≈ 1. 2115: 2043:Yukawa–Tsuno equation 2031:Swain–Lupton equation 2025:Hammett modifications 2004:type reaction over a 1995: 1978: 1939:Rate acceleration EWG 1938: 1921:rate-determining step 1914:Rate acceleration EDG 1913: 1476: 1287: 1248: 1098: 869: 719:p-hydroxybenzoic acid 488: 466:Substituent constants 457: 417: 374: 342: 267: 235: 202: 200:{\displaystyle \rho } 180: 158: 123: 37:equilibrium constants 3187:John Shorter, 1982, 3180:L.P. Hammett, 1970, 1880:improve this section 1860:to meet Knowledge's 1607:ranges are too broad 1160: 1013: 939:improve this section 472:chemical equilibrium 426: 386: 354: 302: 274:substituent constant 247: 222: 216:equilibrium constant 191: 169: 163:= Reference constant 138: 83: 3099:2005IJQC..103..509T 3062:1976CPL....40..175L 2998:10.1021/ja00506a025 2970:10.1021/jo01305a045 2936:10.1021/ja00986a018 2836:10.1021/ja01105a045 2800:1938JChPh...6..506K 2772:10.1021/ja01877a012 2715:10.1021/cr00002a004 2651:10.1021/cr60056a010 2618:10.1021/ja01280a022 2575:2008JChEd..85..558K 1996:Change in emchanism 1578:dielectric constant 1532:Ionization of acids 1360:. If the value of: 1327:Ketone halogenation 1310:the acid catalyzed 1267:alkaline hydrolysis 1177: 1030: 854:resonance structure 726:p-aminobenzoic acid 503: 233:{\displaystyle {K}} 52:Louis Plack Hammett 27:describes a linear 3230:N. Chapman, 2012, 3194:Otto Exner, 1988, 2281:is defined by eq. 2117: 1998: 1981: 1941: 1925:reaction mechanism 1916: 1479: 1464:phenylacetic acids 1429:(mesomeric) effect 1290: 1243: 1163: 1136:constants of the S 1093: 1016: 872: 792:ortho-substituents 493: 491: 452: 412: 369: 337: 262: 242:reference constant 230: 197: 175: 153: 118: 3266:Bull. Hist. Chem. 3107:10.1002/qua.20533 3050:Chem. Phys. Lett. 3026:10.1021/jo0205356 2986:J. Am. Chem. Soc. 2964:(17): 3539–3540. 2924:J. Am. Chem. Soc. 2900:10.1021/jo035854r 2824:J. Am. Chem. Soc. 2808:10.1063/1.1750302 2760:J. Am. Chem. Soc. 2606:J. Am. Chem. Soc. 2583:10.1021/ed085p558 2325: 2324: 2261: 2260: 2166:-Z, where Z is a 2156: 2155: 2123:) in substituted 2110: 2109: 2102: 1946:In the case of a 1908: 1907: 1900: 1862:quality standards 1853:This section may 1790: 1789: 1641: 1640: 1633: 1573: 1572: 1335:hydrochloric acid 1307:in water (+2.008) 1263:organic reactions 1237: 1233: 1221: 1192: 1132:are based on the 1087: 1083: 1071: 1042: 975: 974: 967: 710: 709: 450: 410: 350:In this equation 326: 107: 71:chemical kinetics 63:Gibbs free energy 43:derivatives with 21:organic chemistry 3319: 3273: 3262: 3191:Chichester 1982. 3111: 3110: 3080: 3074: 3073: 3044: 3038: 3037: 3008: 3002: 3001: 2980: 2974: 2973: 2951: 2940: 2939: 2918: 2912: 2911: 2894:(7): 2436–2441. 2878: 2872: 2859: 2853: 2846: 2840: 2839: 2830:(9): 2167–2173. 2818: 2812: 2811: 2782: 2776: 2775: 2766:(8): 1977–1980. 2754: 2748: 2733: 2727: 2726: 2696: 2690: 2689: 2670:. Plenum Press. 2661: 2655: 2654: 2633: 2622: 2621: 2600: 2587: 2586: 2557: 2551: 2528: 2512: 2508: 2451: 2439: 2427: 2415: 2403: 2391: 2373: 2336: 2330: 2319: 2310: 2290: 2280: 2277:. The parameter 2255: 2227: 2150: 2141: 2130: 2105: 2098: 2094: 2091: 2085: 2061: 2060: 2053: 2016: 1971: 1959: 1930:transition state 1903: 1896: 1892: 1889: 1883: 1848: 1847: 1840: 1643: 1642: 1636: 1629: 1625: 1622: 1616: 1596: 1588: 1515: 1514: 1496:potential energy 1484:aromatic systems 1433:Inductive effect 1342:benzyl chlorides 1252: 1250: 1249: 1244: 1242: 1238: 1236: 1235: 1234: 1231: 1224: 1223: 1222: 1219: 1212: 1203: 1202: 1193: 1185: 1176: 1171: 1155: 1102: 1100: 1099: 1094: 1092: 1088: 1086: 1085: 1084: 1081: 1074: 1073: 1072: 1069: 1062: 1053: 1052: 1043: 1035: 1029: 1024: 970: 963: 959: 956: 950: 919: 911: 838:mesomeric effect 834:inductive effect 823:mesomeric effect 819:inductive effect 733: 722: 504: 492: 461: 459: 458: 453: 451: 449: 448: 436: 421: 419: 418: 413: 411: 409: 408: 396: 378: 376: 375: 370: 368: 367: 362: 346: 344: 343: 338: 327: 325: 324: 312: 279: 271: 269: 268: 263: 261: 260: 255: 239: 237: 236: 231: 229: 206: 204: 203: 198: 184: 182: 181: 176: 162: 160: 159: 154: 152: 151: 146: 127: 125: 124: 119: 108: 106: 105: 93: 25:Hammett equation 3327: 3326: 3322: 3321: 3320: 3318: 3317: 3316: 3297: 3296: 3260: 3252: 3205: 3177: 3124: 3119: 3117:Further reading 3114: 3081: 3077: 3045: 3041: 3009: 3005: 2981: 2977: 2952: 2943: 2919: 2915: 2879: 2875: 2860: 2856: 2847: 2843: 2819: 2815: 2783: 2779: 2755: 2751: 2734: 2730: 2697: 2693: 2678: 2662: 2658: 2634: 2625: 2601: 2590: 2558: 2554: 2529: 2525: 2521: 2516: 2515: 2509: 2505: 2500: 2487: 2462: 2455: 2452: 2443: 2440: 2431: 2428: 2419: 2416: 2407: 2404: 2395: 2392: 2371: 2365: 2358: 2354: 2344: 2340: 2332: 2328: 2293: 2278: 2245: 2241: 2237: 2233: 2223: 2219: 2215: 2211: 2201: 2197: 2177: 2173: 2165: 2161: 2139: 2133: 2106: 2095: 2089: 2086: 2072:Please help by 2071: 2062: 2058: 2051: 2027: 1904: 1893: 1887: 1884: 1877: 1849: 1845: 1838: 1831: 1827: 1823: 1819: 1815: 1811: 1803: 1799: 1731: 1727: 1723: 1674: 1667: 1661: 1655: 1637: 1626: 1620: 1617: 1614: 1605:page references 1597: 1586: 1513: 1493: 1416: 1280: 1259: 1230: 1229: 1225: 1218: 1217: 1213: 1211: 1207: 1198: 1194: 1184: 1172: 1167: 1161: 1158: 1157: 1153: 1149: 1145: 1141: 1139: 1130: 1119: 1112: 1080: 1079: 1075: 1068: 1067: 1063: 1061: 1057: 1048: 1044: 1034: 1025: 1020: 1014: 1011: 1010: 1007: 1000: 989: 982: 971: 960: 954: 951: 936: 920: 909: 905: 898: 737: 731: 724: 717: 715: 678:Trifluoromethyl 468: 444: 440: 435: 427: 424: 423: 404: 400: 395: 387: 384: 383: 363: 358: 357: 355: 352: 351: 320: 316: 311: 303: 300: 299: 277: 256: 251: 250: 248: 245: 244: 225: 223: 220: 219: 192: 189: 188: 170: 167: 166: 147: 142: 141: 139: 136: 135: 101: 97: 92: 84: 81: 80: 67:thermochemistry 45:meta- and para- 17: 12: 11: 5: 3325: 3315: 3314: 3309: 3295: 3294: 3284: 3274: 3251: 3248: 3247: 3246: 3228: 3204: 3201: 3200: 3199: 3192: 3185: 3176: 3173: 3172: 3171: 3157: 3143: 3123: 3120: 3118: 3115: 3113: 3112: 3093:(5): 509–515. 3075: 3039: 3020:(25): 8970–4. 3003: 2975: 2941: 2913: 2873: 2868::965-971, see 2854: 2841: 2813: 2788:J. Chem. Phys. 2777: 2749: 2728: 2709:(2): 165–195. 2691: 2676: 2656: 2645:(1): 125–136. 2623: 2588: 2563:J. Chem. Educ. 2552: 2522: 2520: 2517: 2514: 2513: 2502: 2501: 2499: 2496: 2495: 2494: 2489: 2485: 2478: 2473: 2468: 2461: 2458: 2457: 2456: 2453: 2446: 2444: 2441: 2434: 2432: 2429: 2422: 2420: 2417: 2410: 2408: 2405: 2398: 2396: 2393: 2386: 2376: 2375: 2363: 2356: 2352: 2342: 2338: 2323: 2322: 2313: 2311: 2259: 2258: 2249: 2247: 2243: 2239: 2235: 2231: 2221: 2217: 2213: 2209: 2199: 2195: 2175: 2171: 2163: 2159: 2154: 2153: 2144: 2142: 2137: 2108: 2107: 2065: 2063: 2056: 2050: 2047: 2026: 2023: 2018: 2017: 1973: 1972: 1961: 1960: 1906: 1905: 1852: 1850: 1843: 1837: 1834: 1829: 1825: 1821: 1817: 1813: 1809: 1801: 1797: 1788: 1787: 1784: 1781: 1778: 1775: 1772: 1768: 1767: 1764: 1761: 1758: 1755: 1752: 1748: 1747: 1744: 1741: 1738: 1735: 1732: 1729: 1725: 1721: 1717: 1716: 1713: 1710: 1707: 1704: 1701: 1697: 1696: 1693: 1690: 1687: 1684: 1681: 1677: 1676: 1672: 1669: 1665: 1662: 1659: 1656: 1653: 1650: 1647: 1639: 1638: 1600: 1598: 1591: 1585: 1582: 1571: 1570: 1567: 1564: 1561: 1557: 1556: 1553: 1550: 1547: 1543: 1542: 1539: 1536: 1533: 1529: 1528: 1525: 1522: 1519: 1512: 1509: 1491: 1468:carboxyl group 1455: 1454: 1452:electrostatics 1436: 1430: 1415: 1412: 1387: 1386: 1380: 1374: 1368: 1350: 1349: 1338: 1319: 1312:esterification 1308: 1301: 1278: 1271:ethyl benzoate 1258: 1255: 1241: 1228: 1216: 1210: 1206: 1201: 1197: 1191: 1188: 1183: 1180: 1175: 1170: 1166: 1151: 1147: 1143: 1137: 1128: 1117: 1110: 1091: 1078: 1066: 1060: 1056: 1051: 1047: 1041: 1038: 1033: 1028: 1023: 1019: 1005: 1002:with those of 998: 987: 980: 973: 972: 923: 921: 914: 908: 903: 896: 891: 796:steric effects 735: 729: 713: 708: 707: 704: 701: 697: 696: 693: 690: 686: 685: 682: 679: 675: 674: 671: 668: 667:Ethoxycarbonyl 664: 663: 660: 657: 653: 652: 649: 646: 642: 641: 638: 635: 631: 630: 627: 624: 620: 619: 616: 613: 609: 608: 605: 602: 601:Trimethylsilyl 598: 597: 594: 591: 587: 586: 583: 580: 576: 575: 572: 569: 565: 564: 561: 558: 554: 553: 550: 547: 543: 542: 539: 536: 532: 531: 528: 525: 521: 520: 514: 508: 467: 464: 447: 443: 439: 434: 431: 407: 403: 399: 394: 391: 366: 361: 348: 347: 336: 333: 330: 323: 319: 315: 310: 307: 293:reaction rates 259: 254: 228: 212: 211: 196: 186: 174: 164: 150: 145: 129: 128: 117: 114: 111: 104: 100: 96: 91: 88: 33:reaction rates 15: 9: 6: 4: 3: 2: 3324: 3313: 3310: 3308: 3305: 3304: 3302: 3292: 3289: 3285: 3282: 3279: 3275: 3271: 3268: 3267: 3259: 3254: 3253: 3244: 3241: 3237: 3233: 3229: 3226: 3223: 3219: 3215: 3211: 3207: 3206: 3197: 3193: 3190: 3186: 3183: 3179: 3178: 3169: 3166: 3162: 3158: 3155: 3152: 3148: 3144: 3141: 3138: 3134: 3130: 3126: 3125: 3108: 3104: 3100: 3096: 3092: 3088: 3087: 3079: 3071: 3067: 3063: 3059: 3055: 3052: 3051: 3043: 3035: 3031: 3027: 3023: 3019: 3016: 3015: 3014:J. Org. Chem. 3007: 2999: 2995: 2991: 2988: 2987: 2979: 2971: 2967: 2963: 2960: 2959: 2958:J. Org. Chem. 2950: 2948: 2946: 2937: 2933: 2929: 2926: 2925: 2917: 2909: 2905: 2901: 2897: 2893: 2890: 2889: 2888:J. Org. Chem. 2884: 2877: 2870: 2867: 2864: 2858: 2851: 2845: 2837: 2833: 2829: 2826: 2825: 2817: 2809: 2805: 2801: 2797: 2793: 2790: 2789: 2781: 2773: 2769: 2765: 2762: 2761: 2753: 2746: 2742: 2738: 2732: 2724: 2720: 2716: 2712: 2708: 2705: 2704: 2695: 2687: 2683: 2679: 2677:9780306410871 2673: 2669: 2668: 2660: 2652: 2648: 2644: 2641: 2640: 2632: 2630: 2628: 2619: 2615: 2612:(1): 96–103. 2611: 2608: 2607: 2599: 2597: 2595: 2593: 2584: 2580: 2576: 2572: 2568: 2565: 2564: 2556: 2550: 2546: 2542: 2538: 2537: 2532: 2527: 2523: 2507: 2503: 2493: 2490: 2488: 2484: 2479: 2477: 2474: 2472: 2469: 2467: 2464: 2463: 2450: 2445: 2438: 2433: 2426: 2421: 2414: 2409: 2402: 2397: 2390: 2385: 2384: 2383: 2381: 2370: 2369: 2368: 2366: 2359: 2348: 2335: 2321: 2314: 2312: 2308: 2304: 2300: 2296: 2292: 2291: 2288: 2286: 2285: 2276: 2272: 2268: 2267: 2257: 2250: 2248: 2229: 2228: 2225: 2207: 2206: 2193: 2189: 2185: 2181: 2169: 2152: 2145: 2143: 2140: 2132: 2131: 2128: 2127:derivatives. 2126: 2122: 2114: 2104: 2101: 2093: 2083: 2079: 2075: 2069: 2066:This section 2064: 2055: 2054: 2046: 2044: 2040: 2036: 2035:Taft equation 2032: 2022: 2015: 2011: 2010: 2009: 2007: 2003: 1994: 1990: 1987: 1977: 1970: 1966: 1965: 1964: 1958: 1954: 1953: 1952: 1949: 1944: 1937: 1933: 1931: 1926: 1922: 1912: 1902: 1899: 1891: 1881: 1876: 1874: 1870: 1863: 1859: 1858: 1851: 1842: 1841: 1833: 1807: 1795: 1785: 1782: 1779: 1776: 1773: 1770: 1769: 1765: 1762: 1759: 1756: 1753: 1750: 1749: 1745: 1742: 1739: 1736: 1733: 1719: 1718: 1714: 1711: 1708: 1705: 1702: 1699: 1698: 1694: 1691: 1688: 1685: 1682: 1679: 1678: 1670: 1663: 1657: 1651: 1648: 1645: 1644: 1635: 1632: 1624: 1612: 1608: 1606: 1599: 1595: 1590: 1589: 1581: 1579: 1568: 1565: 1562: 1559: 1558: 1554: 1551: 1548: 1545: 1544: 1540: 1537: 1534: 1531: 1530: 1526: 1523: 1520: 1517: 1516: 1508: 1505: 1504:entropy terms 1501: 1498:and that the 1497: 1487: 1485: 1475: 1471: 1469: 1465: 1461: 1453: 1449: 1445: 1441: 1437: 1434: 1431: 1428: 1425: 1424: 1423: 1421: 1411: 1408: 1403: 1401: 1397: 1392: 1384: 1381: 1378: 1375: 1372: 1369: 1366: 1363: 1362: 1361: 1359: 1355: 1347: 1343: 1339: 1336: 1332: 1328: 1324: 1323:acetophenones 1320: 1317: 1313: 1309: 1306: 1302: 1299: 1298:cinnamic acid 1295: 1294: 1293: 1286: 1282: 1276: 1275:reaction rate 1272: 1268: 1264: 1254: 1239: 1226: 1214: 1208: 1204: 1199: 1195: 1189: 1186: 1181: 1178: 1173: 1168: 1164: 1135: 1131: 1124: 1120: 1113: 1104: 1089: 1076: 1064: 1058: 1054: 1049: 1045: 1039: 1036: 1031: 1026: 1021: 1017: 1008: 1001: 994: 990: 983: 969: 966: 958: 948: 944: 940: 934: 933: 929: 924:This section 922: 918: 913: 912: 906: 899: 890: 887: 885: 881: 877: 868: 864: 862: 858: 855: 851: 847: 842: 839: 835: 831: 826: 824: 820: 816: 812: 808: 804: 799: 797: 793: 789: 785: 781: 777: 773: 769: 765: 761: 757: 756:dimethylamino 753: 749: 745: 741: 727: 720: 705: 702: 699: 698: 694: 691: 688: 687: 683: 680: 677: 676: 672: 669: 666: 665: 661: 658: 655: 654: 650: 647: 644: 643: 639: 636: 633: 632: 628: 625: 622: 621: 617: 614: 611: 610: 606: 603: 600: 599: 596:−0.069 595: 592: 589: 588: 584: 581: 578: 577: 573: 570: 567: 566: 562: 559: 556: 555: 551: 548: 545: 544: 541:−0.161 540: 537: 534: 533: 530:−0.211 529: 526: 524:Dimethylamino 523: 522: 518: 515: 512: 509: 506: 505: 501: 497: 487: 483: 481: 477: 473: 463: 445: 441: 437: 432: 429: 405: 401: 397: 392: 389: 380: 364: 359: 334: 331: 328: 321: 317: 313: 308: 305: 298: 297: 296: 294: 289: 287: 284: 280: 275: 257: 252: 243: 226: 217: 214:relating the 210: 194: 187: 172: 165: 148: 143: 134: 133: 132: 115: 112: 109: 102: 98: 94: 89: 86: 79: 78: 77: 74: 72: 68: 64: 60: 55: 53: 49: 46: 42: 38: 34: 30: 26: 22: 3287: 3280: 3278:Chem. Listy, 3277: 3269: 3264: 3231: 3213: 3209: 3195: 3188: 3181: 3128: 3090: 3084: 3078: 3053: 3048: 3042: 3017: 3012: 3006: 2992:(12): 3288. 2989: 2984: 2978: 2961: 2956: 2930:(10): 2342. 2927: 2922: 2916: 2891: 2886: 2882: 2876: 2865: 2862: 2857: 2849: 2844: 2827: 2822: 2816: 2791: 2786: 2780: 2763: 2758: 2752: 2736: 2731: 2706: 2701: 2694: 2666: 2659: 2642: 2637: 2609: 2604: 2566: 2561: 2555: 2534: 2526: 2506: 2482: 2379: 2377: 2361: 2350: 2333: 2326: 2315: 2306: 2302: 2298: 2294: 2282: 2274: 2270: 2264: 2262: 2251: 2203: 2157: 2146: 2135: 2120: 2118: 2096: 2087: 2074:spinning off 2067: 2028: 2019: 1999: 1986:SN2 reaction 1982: 1962: 1945: 1942: 1917: 1894: 1885: 1878:Please help 1865: 1854: 1836:Nonlinearity 1791: 1627: 1618: 1610: 1602: 1574: 1488: 1480: 1456: 1419: 1417: 1406: 1404: 1399: 1395: 1390: 1388: 1382: 1376: 1370: 1364: 1357: 1353: 1351: 1291: 1260: 1156:, we define 1133: 1126: 1122: 1115: 1108: 1105: 1003: 996: 992: 985: 978: 976: 961: 952: 937:Please help 925: 901: 894: 888: 873: 856: 849: 845: 843: 827: 800: 787: 739: 721:(R=OH, R'=H) 711: 607:−0.04 593:−0.170 571:−0.268 552:−0.34 516: 510: 499: 495: 476:benzoic acid 469: 381: 349: 290: 282: 273: 241: 213: 130: 75: 56: 48:substituents 41:benzoic acid 24: 18: 3212:Vol. 11 of 2168:substituent 1882:if you can. 1646:Substituent 1444:substituent 1442:or dipolar 1371:0<ρ<1 1331:acetic acid 604:−0.07 582:−0.25 560:−0.37 549:−0.51 538:−0.66 527:−0.83 507:Substituent 3301:Categories 3240:1461588316 3222:3527613110 3165:0470084944 3151:0306468565 3137:0060440848 3056:(2): 175. 2794:(9): 506. 2745:1891389319 2703:Chem. Rev. 2686:1064985344 2639:Chem. Rev. 2569:(4): 558. 2519:References 2471:Craig plot 2382:constant. 2194:) in p-F-C 2170:such as NH 2078:relocating 2041:, and the 955:March 2020 546:Butylamino 382:A plot of 3312:Equations 3283::210-214. 2090:June 2015 1888:June 2015 1873:WP:VERIFY 1820:and σ’ (σ 1621:June 2015 1611:incorrect 1427:Resonance 1257:Rho value 1205:⁡ 1182:− 1165:σ 1150:O → ArCMe 1055:⁡ 1027:− 1018:σ 926:does not 907:constants 433:⁡ 393:⁡ 335:ρ 332:σ 309:⁡ 195:ρ 173:σ 116:ρ 113:σ 90:⁡ 31:relating 3272:: 48–56. 3034:12467416 2908:15049643 2723:97583278 2511:theory". 2460:See also 2134:ΔCEBE ≈ 1855:require 1828:and σ’(σ 1518:Reaction 1337:(+0.417) 1329:) in an 1318:(-0.085) 1154:OH + HCl 846:scheme 3 830:halogens 811:hydrogen 772:chlorine 764:fluorine 3250:History 3122:General 3095:Bibcode 3058:Bibcode 2796:Bibcode 2571:Bibcode 2125:benzene 1857:cleanup 1766:−0.063 1715:−0.269 1460:benzoic 1448:solvent 1346:acetone 1333:/water/ 1316:ethanol 1305:phenols 947:removed 932:sources 876:methoxy 861:quinoid 815:acidity 768:bromine 748:methoxy 732:, R'=H) 706:+0.710 662:+0.353 651:+0.393 640:+0.373 629:+0.337 585:+0.015 574:+0.115 568:Methoxy 557:Hydroxy 519:effect 3242:, see 3238: 3224:, see 3220: 3175:Theory 3167:, see 3163: 3153:, see 3149: 3139:, see 3135: 3032: 2906: 2743: 2721: 2684: 2674: 2327:where 2190:), C4( 2186:), C3( 2182:), C2( 2037:, the 2033:, the 1786:0.029 1763:−0.222 1746:0.037 1712:−0.624 1706:−0.341 1675:− σ’ 1500:steric 1420:static 1383:ρ<0 1365:ρ>1 1146:Cl + H 884:methyl 880:ethoxy 852:, one 825:(-M). 776:iodine 760:methyl 752:ethoxy 703:+0.778 695:+0.56 684:+0.43 673:+0.37 659:+0.276 648:+0.232 637:+0.227 634:Chloro 626:+0.062 623:Fluoro 618:0.000 590:Methyl 579:Ethoxy 563:+0.12 513:effect 131:where 23:, the 3261:(PDF) 2719:S2CID 2531:IUPAC 2498:Notes 2297:= 2.3 2184:ortho 1869:WP:OR 1812:and σ 1800:and σ 1783:0.077 1780:0.608 1777:0.656 1774:0.579 1760:0.391 1757:0.232 1754:0.454 1743:0.105 1740:0.334 1737:0.402 1734:0.297 1709:0.014 1703:0.283 1668:− σ’ 1566:0.937 1563:0.698 1552:2.494 1538:1.464 1535:1.464 1490:log(K 1440:polar 1142:ArCMe 859:is a 807:nitro 803:cyano 784:cyano 780:nitro 744:amine 728:(R=NH 700:Nitro 692:+0.66 689:Cyano 681:+0.54 670:+0.45 645:Bromo 615:0.000 535:Amino 517:meta- 511:para- 3236:ISBN 3218:ISBN 3161:ISBN 3147:ISBN 3133:ISBN 3030:PMID 2904:PMID 2741:ISBN 2682:OCLC 2672:ISBN 2360:and 2331:and 2192:para 2188:meta 2180:ipso 2174:, NO 1830:meta 1826:meta 1822:para 1818:para 1814:para 1810:meta 1802:para 1798:meta 1796:), σ 1673:meta 1666:para 1660:meta 1654:para 1603:its 1549:2.24 1502:and 1462:and 1190:4.54 1134:rate 1123:para 1040:2.11 993:para 930:any 928:cite 900:and 893:The 878:and 805:and 782:and 656:Iodo 612:None 500:meta 498:and 496:para 35:and 3103:doi 3091:103 3066:doi 3022:doi 2994:doi 2990:101 2966:doi 2932:doi 2896:doi 2832:doi 2804:doi 2768:doi 2711:doi 2647:doi 2614:doi 2579:doi 2545:doi 2543:". 2355:, σ 2076:or 2006:SN2 2002:SN1 1923:or 1871:or 1649:σ’ 1609:or 1569:24 1555:28 1541:54 1377:ρ=0 1344:in 1269:of 1196:log 1046:log 941:by 723:or 478:or 430:log 390:log 306:log 87:log 69:or 19:In 3303:: 3281:94 3270:19 3263:. 3101:. 3089:. 3064:. 3054:40 3028:. 3018:67 2962:45 2944:^ 2928:89 2902:. 2892:69 2866:32 2828:75 2802:. 2764:61 2717:. 2707:91 2680:. 2643:17 2626:^ 2610:59 2591:^ 2577:. 2567:85 2533:, 2305:- 2299:kT 2287:: 2275:σp 2246:) 2224:. 2136:κσ 1771:CN 1751:Br 1720:CO 1700:OH 1695:0 1580:D 1527:D 1521:ρ' 1486:. 1200:10 1103:. 1050:10 857:1b 850:1a 798:. 778:, 774:, 770:, 766:, 762:, 758:, 754:, 750:, 746:, 218:, 207:= 3109:. 3105:: 3097:: 3072:. 3068:: 3060:: 3036:. 3024:: 3000:. 2996:: 2972:. 2968:: 2938:. 2934:: 2910:. 2898:: 2883:O 2838:. 2834:: 2810:. 2806:: 2798:: 2792:6 2774:. 2770:: 2747:. 2725:. 2713:: 2688:. 2653:. 2649:: 2620:. 2616:: 2585:. 2581:: 2573:: 2547:: 2486:a 2483:K 2481:p 2380:σ 2372:κ 2364:p 2362:σ 2357:m 2353:o 2351:σ 2343:4 2341:H 2339:6 2334:ρ 2329:ρ 2320:) 2318:3 2316:( 2309:) 2307:ρ 2303:ρ 2301:( 2295:κ 2284:3 2279:κ 2271:κ 2266:1 2256:) 2254:2 2252:( 2244:5 2242:H 2240:6 2236:4 2234:H 2232:6 2222:5 2220:H 2218:6 2214:4 2212:H 2210:6 2205:1 2200:4 2198:H 2196:6 2176:2 2172:2 2164:4 2162:H 2160:6 2151:) 2149:1 2147:( 2138:p 2121:σ 2103:) 2097:( 2092:) 2088:( 2084:. 2070:. 1901:) 1895:( 1890:) 1886:( 1875:. 1730:5 1728:H 1726:2 1724:C 1722:2 1692:0 1689:0 1686:0 1683:0 1680:H 1671:σ 1664:σ 1658:σ 1652:σ 1634:) 1628:( 1623:) 1619:( 1613:. 1524:ρ 1492:A 1407:ρ 1400:ρ 1396:σ 1391:ρ 1358:ρ 1354:ρ 1325:( 1279:0 1277:k 1240:) 1232:H 1227:k 1220:X 1215:k 1209:( 1187:1 1179:= 1174:+ 1169:p 1152:2 1148:2 1144:2 1138:N 1129:p 1127:σ 1118:p 1116:σ 1111:p 1109:σ 1090:) 1082:H 1077:K 1070:X 1065:K 1059:( 1037:1 1032:= 1022:p 1006:p 1004:σ 999:p 997:σ 988:p 986:σ 981:p 979:σ 968:) 962:( 957:) 953:( 949:. 935:. 904:p 902:σ 897:p 895:σ 736:0 730:2 714:0 446:0 442:k 438:k 406:0 402:K 398:K 365:0 360:k 329:= 322:0 318:k 314:k 286:ρ 278:σ 258:0 253:K 227:K 149:0 144:K 110:= 103:0 99:K 95:K

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