Reactions of fluoroalk-1-en-1-yltrifluoroborate and perfluoroalk-1-yn-1-yltrifluoroborate salts and selected hydrocarbon analogues with hydrogen fluoride and with halogenating agents in aHF and in basic solvents

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• 作者：Vadim V. Bardin^a ; Nicolay Yu. Adonin^a ; ^b ; Hermann-Josef Frohn^c ; ^{h-j.frohn@uni-due.de}
• 关键词：Organyltrifluoroborate salts ; Halogenation ; Halodeboration ; Halofluorination ; NMR spectroscopy
• 刊名：Journal of Fluorine Chemistry
• 出版年：2012
• 出版时间：March, 2012
• 年：2012
• 卷：135
• 期：Complete
• 页码：114-128
• 全文大小：646 K

文摘

The relative rate of the electrophilic hydrodeboration of K[R¡äBF₃] with HF (27-100 % ) diminishes in the series R?#xA0;= C₄H₉CC > C₄F₉CFCFCC > CF₂C(CF₃) > C₃F₇CC ?#xA0;(CF₃)₂CFCC > CF₃CC. When R?#xA0;= CF₃CC the new salt K[CF₃CH₂-CF₂BF₃] was obtained by addition of HF besides CF₃CCH and K[BF₄]. Small amounts of water caused the formation of K[CF₃CH₂-C(O)BF₃] as a by-product. The electrophilic halofluorination of perfluoroalkenyltrifluoroborate salts with NCS or NBS in aHF (anhydrous HF) led to K[R_FCFHal-CF₂BF₃] (from K[R_FCFCFBF₃]) and K[R_FCHal₂-CF₂BF₃] (from K[R_FCHalCFBF₃] and K[R_FCCBF₃]) (Hal = Cl, Br). Treatment of K[R_FCFCFBF₃] and K[R_FCCBF₃] with 5 % F₂/N₂ in MeCN gave the corresponding salts K[R_FCF₂-CF₂BF₃] in 16-25 % isolated yield. Reactions of K[trans-C₄F₉CFCFBF₃] with Cl₂ in MeOH resulted in K[C₄F₉CFCl-C(O)BF₃] (major product). The latter was also obtained in reactions of K[trans-C₄F₉CFCFBF₃] with Cl₂ in MeCN or sulfolane after sequential methanolysis of the primarily formed products. In contrast, the salts K[RCFCFBF₃] (R = C_nF_2n+1, trans-C₄H₉) and K[CF₃CCBF₃] underwent bromodeboration to RCFCFBr and CF₃CCBr, respectively, when they were reacted with bromine in the polar solvents MeOH, MeCN, or sulfolane.