Electrochemical oxidation of silacyclopentadienes (siloles)

The cyclic voltammetry of sixteen 2,3,4,5-tetraphenyl-1-silacyclopentadienes [1,1-dihydro- (I); 1-chloro-1-hydro- (II); 1-chloro-1-phenyl- (III); 1,1-dichloro- (IV); 1-chloro-1-methyl- (V); 1-chloro-1-phenyl- (VI); 1-chloro-1-(phenylacetylene)- (VII); 1,1-dimethyl- (VIII); 1-methyl-1-phenyl- (IX); 1,1-bis(trimethylsilyl)- (X); 1,1-bis(trimethylstannyl)- (XI); four bicyclic compounds of 2,2′,3,3′,4,4′,5,5′-octaphenyl bisiloles bonded through Si–Si bonds (1,1′-dimethyl- (XII); 1,1′-diphenyl- (XIII); 1,1′-dibenzyl- (XIV) and 1,1′-bis(trimethylstannyl)- (XV), and a spiro derivative XVI] have been investigated. In addition, preparative electrochemical oxidation of selected examples (IV–VI, VIII, IX, XII and XIII) has been carried out under controlled-potential conditions.