Electrosynthesis in a microemulsion using a novel cobaloxime catalyst

[Bis[mu-[(2,3-butanedione dioximato) (2-)-O:O']]tetrafluorodiborato(2-)-N,N',N ",N "']cobalt (COBF, 1) was used as a catalyst for the conversion of trans-1,2-dibromocyclohexane (DBCH) to cyclohexene and the photoelectrochemical cyclisation of 2-(4-bromobutyl)-2-cyclohexen-1-one (BBC) to trans-1-decalone 2 in a microemulsion. Voltammetry showed clear evidence of catalytic behaviour and bulk electrolysis showed larger turnover numbers for both reactions when compared with the same system using vitamin B-12a as catalyst. For BBC, improved turnover may result from a relatively weak carbon-cobalt bond in the alkylcobalt intermediate of 1, and from better partition of 1 into the organic phase in which reactant BBC resides. (C) 1999 Elsevier Science S.A. All rights reserved.