Synthesis and Properties of Arylvinylidene-Bridged Triphenylamines

A series of arylvinylidene-bridged
triphenylamines were efficiently
synthesized through the thionation/Barton–Kellogg olefination
sequence from their corresponding carbonyl precursors. The electrochemical
investigations identified these highly distorted scaffolds as fairly
strong electron donors capable of several reversible oxidation steps
with the first oxidation occurring at a potential comparable to that
of ferrocene for the n-hexyl-substituted diphenylvinylidene-bridged
compound.