Indolophanetetrayne cobalt complexes via Nicholas reactions

Org Lett. 2003 Apr 3;5(7):1003-5. doi: 10.1021/ol027564n.

Abstract

[reaction: see text] 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.