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Reoxidant

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81:, some vanadium(III) is reduced to inactive vanadium(II) derivatives. To correct for this reduction, reoxidants such as methyl trichloroacetate are added. The alkyl chloride functions as a source of a chlorine radical, which adds to the inactive V(II) species. In some cases, the reoxidants are called 139:
Timothy J. Donohoe; Katherine M. P. Wheelhouse (née Gosby); Peter J. Lindsay-Scott; Paul A. Glossop; Ian A. Nash; Jeremy S. Parker (2008). "Pyridine-N-Oxide as a Mild Reoxidant Which Transforms Osmium-Catalyzed Oxidative Cyclization".
210:
R. A. Miller; R. S. Hoerrner (2003). "Iodine as a Chemoselective Reoxidant of TEMPO: Application to the Oxidation of Alcohols to Aldehydes and Ketones".
57:. The spent catalyst is an osmium(VI) complex, which reacts with a reoxidant to regenerate Os(VIII). Typical reoxidants for this application include 138: 73:
As catalysts for the polymerization of dienes, vanadium complexes are activated with alkylaluminium chlorides, e.g.
32:
by oxidation. In some cases they are used stoichiometrically, in other cases only small amounts are required.
175:
Kotohiro Nomura; Shu Zhang (2011). "Design of Vanadium Complex Catalysts for Precise Olefin Polymerization".
250: 77:. The organoaluminium reagent installs alkyl groups on the V(III) precatalyst. During catalysis or during 62: 260: 74: 8: 101:
as the reoxidant, TEMPO-H is oxidized back to TEMPO, which then functions catalytically:
78: 255: 227: 192: 157: 97:, is an expensive but effective oxidant for converting alcohols to carbonyls. With 219: 184: 149: 58: 50: 244: 231: 196: 161: 153: 223: 188: 17: 29: 25: 98: 54: 94: 68: 93:(2,2,6,6-Tetramethylpiperidin-1-yl)oxyl, commonly known as 209: 174: 49:
Reoxidants are commonly used in reactions catalyzed by
53:, which is a primary oxidant converting alkenes to 40: 242: 69:Vanadium(III)-based alkene polymerizations 88: 243: 112:OH + 2 TEMPO → RCHO + 2 TEMPO-H 13: 14: 272: 35: 203: 168: 132: 1: 126: 7: 45:-catalyzed dihydroxylations 10: 277: 63:N-methylmorpholine N-oxide 61:, ferricyanide/water, and 75:diethylaluminium chloride 154:10.1002/anie.200705425 89:Oxidations with TEMPO 142:Angew. Chem. Int. Ed 251:Reaction mechanisms 122:→ 2 TEMPO + 2 HI 79:catalyst activation 28:that regenerates a 224:10.1021/ol0272444 189:10.1021/cr100207h 148:(15): 2872–2875. 268: 261:Oxidizing agents 236: 235: 207: 201: 200: 183:(3): 2342–2362. 172: 166: 165: 136: 59:pyridine-N-oxide 51:osmium tetroxide 276: 275: 271: 270: 269: 267: 266: 265: 241: 240: 239: 208: 204: 173: 169: 137: 133: 129: 121: 118:2 TEMPO-H + I 111: 91: 71: 47: 44: 38: 12: 11: 5: 274: 264: 263: 258: 253: 238: 237: 218:(3): 285–287. 202: 167: 130: 128: 125: 124: 123: 119: 113: 109: 90: 87: 70: 67: 46: 42: 39: 37: 34: 9: 6: 4: 3: 2: 273: 262: 259: 257: 254: 252: 249: 248: 246: 233: 229: 225: 221: 217: 213: 206: 198: 194: 190: 186: 182: 178: 171: 163: 159: 155: 151: 147: 143: 135: 131: 117: 114: 107: 104: 103: 102: 100: 96: 86: 84: 80: 76: 66: 64: 60: 56: 52: 33: 31: 27: 23: 19: 215: 211: 205: 180: 176: 170: 145: 141: 134: 116:reoxidation: 115: 105: 92: 83:rejuvenators 82: 72: 48: 36:Applications 21: 15: 245:Categories 127:References 106:oxidation: 256:Catalysis 212:Org. Lett 177:Chem. Rev 22:reoxidant 18:chemistry 232:12556173 197:21033737 162:18324650 30:catalyst 55:glycols 26:reagent 230:  195:  160:  99:iodine 95:TEMPO 24:is a 228:PMID 193:PMID 158:PMID 20:, a 220:doi 185:doi 181:111 150:doi 108:RCH 41:OsO 16:In 247:: 226:. 214:. 191:. 179:. 156:. 146:47 144:. 85:. 65:. 234:. 222:: 216:5 199:. 187:: 164:. 152:: 120:2 110:2 43:4

Index

chemistry
reagent
catalyst
osmium tetroxide
glycols
pyridine-N-oxide
N-methylmorpholine N-oxide
diethylaluminium chloride
catalyst activation
TEMPO
iodine
doi
10.1002/anie.200705425
PMID
18324650
doi
10.1021/cr100207h
PMID
21033737
doi
10.1021/ol0272444
PMID
12556173
Categories
Reaction mechanisms
Catalysis
Oxidizing agents

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