20:
267:
owes its inertness to two factors: (i) it is symmetrical so that the negative charge is distributed equally over four atoms, and (ii) it is composed of highly electronegative fluorine atoms, which diminish the basicity of the anion. In addition to the weakly coordinating nature of the anion,
223:
is also conveniently the smallest weakly coordinating anion from the point of view of equivalent weight, often making it the anion of choice for preparing cationic reagents or catalysts for use in synthesis, in the absence of other substantial differences in chemical or physical factors.
363:, BARF, or ) must be employed. Moreover, in other cases of ostensibly "cationic" complexes, the fluorine atom in fact acts as a bridging ligand between boron and the cationic center. For instance, the gold complex was found crystallographically to contain two Au–F–B bridges.
840:
Cresswell, Alexander J.; Davies, Stephen G.; Roberts, Paul M.; Thomson, James E. (2015-01-28). "Beyond the Balz–Schiemann
Reaction: The Utility of Tetrafluoroborates and Boron Trifluoride as Nucleophilic Fluoride Sources".
804:
Cresswell, Alexander J.; Davies, Stephen G.; Roberts, Paul M.; Thomson, James E. (2015). "Beyond the Balz–Schiemann
Reaction: The Utility of Tetrafluoroborates and Boron Trifluoride as Nucleophilic Fluoride Sources".
1260:
366:
Transition and heavy metal fluoroborates are produced in the same manner as other fluoroborate salts; the respective metal salts are added to reacted boric and hydrofluoric acids.
1605:
1632:
1620:
1314:
1302:
1389:
1174:
1640:
1381:
1561:
1526:
1214:
1569:
1514:
1283:
1349:
754:
Abadie, Marc-Antoine; Trivelli, Xavier; Medina, Florian; Capet, Frédéric; Roussel, Pascal; Agbossou-Niedercorn, Francine; Michon, Christophe (2014-08-01).
756:"Asymmetric Intramolecular Hydroamination of Alkenes in Mild and Wet Conditions—Structure and Reactivity of Cationic Binuclear Gold(I) Catalysts"
1026:
1544:
661:
682:
salt is highly toxic). Most other transition metal tetrafluoroborates only exist as solvates of water, alcohols, ethers, or nitriles.
214:
does not suffer from these problems. Safety considerations, however, overshadow this inconvenience. With a formula weight of 86.8, BF
328:, both of which are even more stable toward hydrolysis and other chemical reactions and whose salts tend to be more lipophilic.
958:
414:
for the synthesis of aryl fluorides is the best known example of such a reaction. Ether and halopyridine adducts of HBF
1482:
1470:
1459:
1447:
1435:
1423:
1412:
1325:
1248:
1237:
1106:
685:
1099:
1848:
1019:
755:
1004:
1294:
1125:
941:
Willem L. Driessen, Jan
Reedijk (1992). "Solid Solvates: The Use of Weak Ligands in Coordination Chemistry".
884:
Guo, Rui; Qi, Xiaotian; Xiang, Hengye; Geaneotes, Paul; Wang, Ruihan; Liu, Peng; Wang, Yi-Ming (2020-06-02).
576:
239:
anion is less nucleophilic and basic (and therefore more weakly coordinating) than nitrates, halides or even
1337:
331:
Extremely reactive cations such as those derived from Ti, Zr, Hf, and Si do in fact abstract fluoride from
1843:
1206:
1132:
1084:
1012:
590:
411:
174:
in the laboratory as a weakly coordinating anion. With organic compounds, especially amine derivatives,
120:, which is used in similar ways in the laboratory. It arises by the reaction of fluoride salts with the
1272:
1143:
1502:
1070:
695:
An electrochemical cycle involving ferrous/ferric tetrafluoroborate is being used to replace thermal
1494:
1166:
675:
255:, it is usually assume that the cation is the reactive agent and this tetrahedral anion is inert.
730:
356:
886:"Stereodivergent Alkyne Hydrofluorination Using Protic Tetrafluoroborates as Tunable Reagents"
131:
503:
Fluoroborate is often used to isolate highly electrophilic cations. Some examples include:
65:
974:
Möller, H.; Lutz, H. D. (2010). "Crystal structure of thallium tetrafluoroborate, TlBF4".
8:
431:
301:
89:
918:
885:
786:
540:
81:
678:
and thallium tetrafluoroborate are convenient halide abstracting agents (although the
991:
954:
923:
905:
866:
858:
822:
778:
419:
139:
124:
790:
104:) and is valence isoelectronic with many stable and important species including the
1051:
983:
946:
913:
897:
850:
814:
770:
735:
511:
987:
704:
580:
19:
1034:
950:
718:
280:
salts are often more soluble in organic solvents (lipophilic) than the related
1837:
995:
909:
862:
782:
714:
584:
558:
507:
61:
927:
901:
870:
826:
774:
700:
481:
383:
1113:
710:
650:
603:
105:
410:
serves as a fluorine source to deliver an equivalent of fluoride. The
199:
135:
121:
854:
818:
398:
Despite the low reactivity of the tetrafluoroborate anion in general,
653:, a fluorination agent, and other N–F electrophilic fluorine sources.
597:
525:
489:
696:
679:
493:
240:
485:
281:
145:
940:
669:
497:
379:
375:
285:
839:
803:
46:
371:
186:
forms potentially explosive derivatives. Disadvantages to
753:
367:
202:
and decomposition via loss of a fluoride ligand, whereas
976:
418:
have been reported to be effective reagents for the
883:
1835:
484:and ammonium ions crystallize as water-soluble
430:Potassium fluoroborate is obtained by treating
146:As an anion in inorganic and organic chemistry
1020:
573:, the strongest commercial alkylating agents.
721:, are often isolated as tetrafluoroborates.
656:Bromonium and iodonium species, including py
386:of these metals in a solution containing HBF
1027:
1013:
973:
917:
18:
890:Angewandte Chemie International Edition
717:salts, ionic liquids and precursors to
434:with boric acid and hydrofluoric acid.
1836:
1060:
1035:Salts and covalent derivatives of the
393:
1724:
1008:
425:
382:fluoroborates are prepared through
13:
945:. Vol. 29. pp. 111–118.
686:Transition metal nitrile complexes
636:, and other cationic metallocenes.
198:include its slight sensitivity to
14:
1860:
355:is not an "innocent" anion and
967:
934:
877:
833:
797:
747:
134:with base, or by treatment of
60:. This tetrahedral species is
1:
988:10.1524/zkri.1992.201.3-4.285
741:
316:, and hexafluoroantimonate,
243:. Thus, when using salts of
162:has led to decreased use of
7:
724:
10:
1865:
1726:
951:10.1002/9780470132609.ch27
357:weakly coordinating anions
1062:
1044:
676:Silver tetrafluoroborate
1849:Non-coordinating anions
412:Balz–Schiemann reaction
902:10.1002/anie.202006278
775:10.1002/cctc.201402350
731:Non-coordinating anion
488:with the exception of
150:The popularization of
39:
132:tetrafluoroboric acid
23:The structure of the
22:
670:diaryliodonium salts
66:tetrafluoroberyllate
943:Inorganic Syntheses
896:(38): 16651–16660.
662:Barluenga's reagent
541:Diazonium compounds
432:potassium carbonate
394:As a fluoride donor
343:, so in such cases
302:hexafluorophosphate
90:tetrafluoroammonium
1844:Tetrafluoroborates
660:X (X = Br; X = I:
288:salts. Related to
82:tetrafluoromethane
40:
1831:
1830:
1825:
1824:
1117:
1037:tetrafluoroborate
960:978-0-470-13260-9
855:10.1021/cr5001805
819:10.1021/cr5001805
559:Meerwein reagents
514:), including H·(H
480:Fluoroborates of
426:Examples of salts
420:hydrofluorination
140:hydrofluoric acid
43:Tetrafluoroborate
25:tetrafluoroborate
1856:
1115:
1048:
1047:
1029:
1022:
1015:
1006:
1005:
1000:
999:
982:(3–4): 285–286.
971:
965:
964:
938:
932:
931:
921:
881:
875:
874:
843:Chemical Reviews
837:
831:
830:
807:Chemical Reviews
801:
795:
794:
769:(8): 2235–2239.
760:
751:
736:Fluoroboric acid
635:
634:
633:
625:
624:
616:
615:
572:
571:
570:
554:
553:
552:
512:fluoroboric acid
409:
408:
407:
354:
353:
352:
342:
341:
340:
327:
326:
325:
315:
314:
313:
299:
298:
297:
279:
278:
277:
266:
265:
264:
254:
253:
252:
238:
237:
236:
222:
221:
213:
212:
211:
197:
196:
195:
185:
184:
183:
173:
172:
171:
161:
160:
159:
119:
118:
117:
103:
102:
101:
79:
78:
77:
59:
58:
57:
38:
37:
36:
1864:
1863:
1859:
1858:
1857:
1855:
1854:
1853:
1834:
1833:
1832:
1827:
1826:
1648:
1644:
1636:
1628:
1624:
1613:
1609:
1577:
1573:
1565:
1552:
1548:
1534:
1530:
1522:
1518:
1510:
1506:
1498:
1490:
1486:
1478:
1474:
1469:
1467:
1463:
1455:
1451:
1443:
1439:
1431:
1427:
1422:
1420:
1416:
1397:
1393:
1385:
1357:
1353:
1345:
1341:
1333:
1329:
1324:
1322:
1318:
1310:
1306:
1298:
1293:
1291:
1287:
1282:
1280:
1276:
1268:
1264:
1256:
1252:
1247:
1245:
1241:
1222:
1218:
1210:
1182:
1178:
1170:
1151:
1147:
1142:
1140:
1136:
1131:
1129:
1121:
1112:
1110:
1105:
1103:
1098:
1096:
1092:
1088:
1074:
1055:
1040:
1033:
1003:
972:
968:
961:
939:
935:
882:
878:
838:
834:
802:
798:
758:
752:
748:
744:
727:
719:stable carbenes
705:Doe Run Company
691:
667:
659:
646:
642:
632:
629:
628:
627:
623:
620:
619:
618:
614:
611:
610:
609:
607:
594:
581:oxidizing agent
579:a one-electron
569:
566:
565:
564:
562:
551:
548:
547:
546:
544:
536:
531:
522:
517:
508:Solvated proton
476:
472:
468:
464:
460:
456:
449:
445:
441:
428:
417:
406:
403:
402:
401:
399:
396:
389:
362:
351:
348:
347:
346:
344:
339:
336:
335:
334:
332:
324:
321:
320:
319:
317:
312:
309:
308:
307:
305:
296:
293:
292:
291:
289:
276:
273:
272:
271:
269:
263:
260:
259:
258:
256:
251:
248:
247:
246:
244:
235:
232:
231:
230:
228:
220:
217:
216:
215:
210:
207:
206:
205:
203:
194:
191:
190:
189:
187:
182:
179:
178:
177:
175:
170:
167:
166:
165:
163:
158:
155:
154:
153:
151:
148:
130:, treatment of
128:
116:
113:
112:
111:
109:
100:
97:
96:
95:
93:
87:
76:
73:
72:
71:
69:
56:
53:
52:
51:
49:
35:
32:
31:
30:
28:
17:
12:
11:
5:
1862:
1852:
1851:
1846:
1829:
1828:
1823:
1822:
1819:
1816:
1813:
1810:
1807:
1804:
1801:
1798:
1795:
1792:
1789:
1786:
1783:
1780:
1776:
1775:
1772:
1769:
1766:
1763:
1760:
1757:
1754:
1751:
1748:
1745:
1742:
1739:
1736:
1733:
1729:
1728:
1725:
1722:
1721:
1718:
1715:
1712:
1709:
1706:
1703:
1700:
1697:
1694:
1691:
1688:
1685:
1682:
1679:
1676:
1673:
1670:
1667:
1663:
1662:
1659:
1656:
1653:
1650:
1646:
1642:
1638:
1634:
1630:
1626:
1622:
1618:
1615:
1611:
1607:
1603:
1600:
1597:
1594:
1591:
1588:
1585:
1582:
1579:
1575:
1571:
1567:
1563:
1558:
1557:
1554:
1550:
1546:
1542:
1539:
1536:
1532:
1528:
1524:
1520:
1516:
1512:
1508:
1504:
1500:
1496:
1492:
1488:
1484:
1480:
1476:
1472:
1465:
1461:
1457:
1453:
1449:
1445:
1441:
1437:
1433:
1429:
1425:
1418:
1414:
1410:
1407:
1404:
1401:
1399:
1395:
1391:
1387:
1383:
1378:
1377:
1374:
1371:
1368:
1365:
1362:
1359:
1355:
1351:
1347:
1343:
1339:
1335:
1331:
1327:
1320:
1316:
1312:
1308:
1304:
1300:
1296:
1289:
1285:
1278:
1274:
1270:
1266:
1262:
1258:
1254:
1250:
1243:
1239:
1235:
1232:
1229:
1226:
1224:
1220:
1216:
1212:
1208:
1203:
1202:
1199:
1196:
1193:
1190:
1187:
1184:
1180:
1176:
1172:
1168:
1163:
1162:
1159:
1156:
1153:
1149:
1145:
1138:
1134:
1127:
1123:
1119:
1108:
1101:
1094:
1090:
1086:
1082:
1079:
1076:
1072:
1067:
1066:
1063:
1061:
1059:
1057:
1053:
1046:
1045:
1042:
1041:
1032:
1031:
1024:
1017:
1009:
1002:
1001:
966:
959:
933:
876:
849:(2): 566–611.
832:
813:(2): 566–611.
796:
745:
743:
740:
739:
738:
733:
726:
723:
693:
692:
689:
683:
673:
665:
657:
654:
648:
644:
640:
637:
630:
621:
612:
601:
592:
588:
574:
567:
556:
549:
538:
534:
529:
520:
515:
478:
477:
474:
470:
466:
462:
458:
454:
451:
447:
443:
439:
427:
424:
415:
404:
395:
392:
387:
360:
349:
337:
322:
310:
294:
274:
261:
249:
233:
218:
208:
192:
180:
168:
156:
147:
144:
126:
114:
98:
85:
74:
54:
33:
15:
9:
6:
4:
3:
2:
1861:
1850:
1847:
1845:
1842:
1841:
1839:
1820:
1817:
1814:
1811:
1808:
1805:
1802:
1799:
1796:
1793:
1790:
1787:
1784:
1781:
1778:
1777:
1773:
1770:
1767:
1764:
1761:
1758:
1755:
1752:
1749:
1746:
1743:
1740:
1737:
1734:
1731:
1730:
1723:
1719:
1716:
1713:
1710:
1707:
1704:
1701:
1698:
1695:
1692:
1689:
1686:
1683:
1680:
1677:
1674:
1671:
1668:
1665:
1664:
1660:
1657:
1654:
1651:
1649:
1639:
1637:
1631:
1629:
1619:
1616:
1614:
1604:
1601:
1598:
1595:
1592:
1589:
1586:
1583:
1580:
1578:
1568:
1566:
1560:
1559:
1555:
1553:
1543:
1540:
1537:
1535:
1525:
1523:
1513:
1511:
1501:
1499:
1493:
1491:
1481:
1479:
1468:
1458:
1456:
1446:
1444:
1434:
1432:
1421:
1411:
1408:
1405:
1402:
1400:
1398:
1388:
1386:
1380:
1379:
1375:
1372:
1369:
1366:
1363:
1360:
1358:
1348:
1346:
1336:
1334:
1323:
1313:
1311:
1301:
1299:
1292:
1281:
1271:
1269:
1259:
1257:
1246:
1236:
1233:
1230:
1227:
1225:
1223:
1213:
1211:
1205:
1204:
1200:
1197:
1194:
1191:
1188:
1185:
1183:
1173:
1171:
1165:
1164:
1160:
1157:
1154:
1152:
1141:
1130:
1124:
1122:
1111:
1104:
1097:
1083:
1080:
1077:
1075:
1069:
1068:
1064:
1058:
1056:
1050:
1049:
1043:
1038:
1030:
1025:
1023:
1018:
1016:
1011:
1010:
1007:
997:
993:
989:
985:
981:
977:
970:
962:
956:
952:
948:
944:
937:
929:
925:
920:
915:
911:
907:
903:
899:
895:
891:
887:
880:
872:
868:
864:
860:
856:
852:
848:
844:
836:
828:
824:
820:
816:
812:
808:
800:
792:
788:
784:
780:
776:
772:
768:
764:
757:
750:
746:
737:
734:
732:
729:
728:
722:
720:
716:
715:formamidinium
712:
708:
706:
702:
698:
687:
684:
681:
677:
674:
671:
663:
655:
652:
649:
638:
605:
602:
599:
595:
589:
586:
585:nitrosylation
582:
578:
575:
560:
557:
542:
539:
537:
527:
523:
513:
509:
506:
505:
504:
501:
499:
495:
491:
487:
483:
482:alkali metals
452:
437:
436:
435:
433:
423:
421:
413:
391:
385:
381:
377:
373:
369:
364:
358:
329:
303:
287:
283:
242:
225:
201:
143:
141:
137:
133:
129:
123:
107:
91:
83:
67:
63:
62:isoelectronic
48:
44:
26:
21:
1036:
979:
975:
969:
942:
936:
893:
889:
879:
846:
842:
835:
810:
806:
799:
766:
762:
749:
709:
703:ores by the
701:lead sulfide
694:
533:
519:
510:(H (solv.),
502:
479:
442:+ 4 HF → HBF
429:
422:of alkynes.
397:
384:electrolysis
365:
330:
226:
149:
42:
41:
24:
763:ChemCatChem
711:Imidazolium
651:Selectfluor
604:Ferrocenium
106:perchlorate
1838:Categories
742:References
688:, e.g. BF
359:(e.g., SbF
200:hydrolysis
136:boric acid
122:Lewis acid
996:2196-7105
910:1521-3773
863:0009-2665
783:1867-3899
598:nitration
528:"), H·(Et
526:hydronium
490:potassium
241:triflates
928:32485005
871:25084541
827:25084541
791:96851116
725:See also
697:smelting
680:thallium
664:) and Ar
600:reagent.
587:reagent.
561:such as
494:rubidium
486:hydrates
1727:
919:8287824
465:→ 2 KBF
282:nitrate
108:anion,
88:), and
45:is the
27:anion,
1284:FeO(BF
994:
957:
926:
916:
908:
869:
861:
825:
789:
781:
498:cesium
496:, and
380:nickel
378:, and
376:copper
286:halide
1641:Pb(BF
1621:Hg(BF
1606:Pt(BF
1570:Ba(BF
1527:Sn(BF
1515:In(BF
1503:Cd(BF
1390:Sr(BF
1350:Zn(BF
1338:Cu(BF
1315:Ni(BF
1303:Co(BF
1273:Fe(BF
1261:Mn(BF
1215:Ca(BF
1175:Mg(BF
787:S2CID
759:(PDF)
453:2 HBF
446:+ 3 H
438:B(OH)
138:with
64:with
47:anion
16:Anion
1633:TlBF
1562:CsBF
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1382:RbBF
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1800:Am
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1779:**
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1720:Og
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1696:Ds
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1690:Hs
1687:Bh
1684:Sg
1681:Db
1678:Rf
1675:Lr
1672:**
1669:Ra
1666:Fr
1661:Rn
1658:At
1655:Po
1652:Bi
1617:Au
1602:Ir
1599:Os
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1590:Ta
1587:Hf
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1549:)BF
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1483:(BF
1471:(BF
1460:(BF
1448:(BF
1436:(BF
1424:(BF
1413:(BF
1409:Nb
1406:Zr
1376:Kr
1373:Br
1370:Se
1367:As
1364:Ge
1361:Ga
1326:(BF
1249:(BF
1238:(BF
1231:Ti
1228:Sc
1207:KBF
1201:Ar
1198:Cl
1189:Si
1186:Al
1161:Ne
1118:)BF
1078:Be
1065:He
1052:HBF
1039:ion
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980:201
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898:doi
851:doi
847:115
815:doi
811:115
771:doi
699:of
668:I (
639:(BF
563:OEt
545:ArN
500:.
469:+ H
457:+ K
368:Tin
318:SbF
284:or
204:ClO
176:ClO
164:ClO
110:ClO
84:(CF
80:),
70:BeF
1840::
1791:U
1732:*
1593:W
1581:*
1403:Y
1295:BF
1234:V
1195:S
1192:P
1158:F
1155:O
1148:BF
1144:NH
1137:BF
1133:NO
1107:BF
1100:BF
1093:BF
1081:B
990:.
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606:,
591:NO
577:NO
555:).
532:O)
524:("
518:O)
492:,
473:CO
461:CO
400:BF
390:.
374:,
370:,
345:BF
333:BF
306:PF
304:,
290:BF
270:BF
257:BF
245:BF
229:BF
188:BF
152:BF
142:.
125:BF
94:NF
50:BF
29:BF
1647:2
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1643:4
1635:4
1627:2
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1623:4
1612:2
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1608:4
1576:2
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1572:4
1564:4
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1517:4
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1505:4
1497:4
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1477:4
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1473:4
1466:3
1464:)
1462:4
1454:2
1452:)
1450:4
1442:4
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1438:4
1430:4
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1426:4
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1415:4
1396:2
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1392:4
1384:4
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1352:4
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1340:4
1332:2
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1328:4
1321:2
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1317:4
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1305:4
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1177:4
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1128:4
1120:4
1114:(
1109:4
1102:4
1095:4
1091:7
1089:H
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1085:C
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1028:e
1021:t
1014:v
998:.
986::
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930:.
900::
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829:.
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767:6
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645:2
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622:5
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613:5
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535:n
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516:2
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471:2
467:4
463:3
459:2
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450:O
448:2
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361:6
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262:4
250:4
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