Indolophanetetrayne Cobalt Complexes via Nicholas Reactions

Abstract

Indole N-substituted diyne tetracobalt complexes (4) undergo a Lewis acid mediated dimerization−cyclization reaction through the indole 3-position to afford indolophanetetrayne cobalt complexes (7). Substitution of the indole fragment of (4) with a 3-methyl function allows analogous formation of indolophanetetrayne complex (9), linked through the indole 2-position.