Selective electrochemical synthesis and reactivity of functional benzylic fluorosilylsynthons
摘要:
Electrochemical reductive silylation of meta-(trifluoromethyl)arenes by the sacrificial anode technique selectively led to meta-trimethylsilyldifluoromethylarenes (ArCF2TMS), in the presence of an excess of TMSCl and in a THF/cosolvent mixture (cosolvent = DMPU or HMPA). In the case of meta-(trimethylsilyldifluoromethyl)trifluoromethylbenzene, the influence of the cosolvent on the silylation selectivity was studied. A cyclic voltammetry study allowed an explanation of the difference in the results obtained between the trifluoromethylbenzene and meta-bistrifluoromethylbenzene series. ArCF2TMS (Ar = Ph, m-CF3C6H4) species were found efficient for ArCF2-group transfer to diverse electrophiles under Fuchigami's conditions (KF catalysis in DMF). (C) 2001 Elsevier Science B.V. All rights reserved.
Selective electrochemical synthesis and reactivity of functional benzylic fluorosilylsynthons
摘要:
Electrochemical reductive silylation of meta-(trifluoromethyl)arenes by the sacrificial anode technique selectively led to meta-trimethylsilyldifluoromethylarenes (ArCF2TMS), in the presence of an excess of TMSCl and in a THF/cosolvent mixture (cosolvent = DMPU or HMPA). In the case of meta-(trimethylsilyldifluoromethyl)trifluoromethylbenzene, the influence of the cosolvent on the silylation selectivity was studied. A cyclic voltammetry study allowed an explanation of the difference in the results obtained between the trifluoromethylbenzene and meta-bistrifluoromethylbenzene series. ArCF2TMS (Ar = Ph, m-CF3C6H4) species were found efficient for ArCF2-group transfer to diverse electrophiles under Fuchigami's conditions (KF catalysis in DMF). (C) 2001 Elsevier Science B.V. All rights reserved.
Irradiation of CF3-substituted benzene in the presence of hexamethyldisilane and octamethyltrisilane causes two types of photosilylation, namely one at a benzylic position to give the corresponding benzylic silanes, and the other at aromatic ring to afford the corresponding phenylsilanes.
Selective electrochemical synthesis and reactivity of functional benzylic fluorosilylsynthons
作者:Philippe Clavel、Guillaume Lessene、Claude Biran、Michel Bordeau、Nicolas Roques、Stéphane Trévin、Dominique de Montauzon
DOI:10.1016/s0022-1139(00)00373-0
日期:2001.2
Electrochemical reductive silylation of meta-(trifluoromethyl)arenes by the sacrificial anode technique selectively led to meta-trimethylsilyldifluoromethylarenes (ArCF2TMS), in the presence of an excess of TMSCl and in a THF/cosolvent mixture (cosolvent = DMPU or HMPA). In the case of meta-(trimethylsilyldifluoromethyl)trifluoromethylbenzene, the influence of the cosolvent on the silylation selectivity was studied. A cyclic voltammetry study allowed an explanation of the difference in the results obtained between the trifluoromethylbenzene and meta-bistrifluoromethylbenzene series. ArCF2TMS (Ar = Ph, m-CF3C6H4) species were found efficient for ArCF2-group transfer to diverse electrophiles under Fuchigami's conditions (KF catalysis in DMF). (C) 2001 Elsevier Science B.V. All rights reserved.