Stereospecific templated synthesis of a triruthenium butadiyne-linked cyclic porphyrin trimer

Abstract

A bis(ethynyl)-substituted porphyrin monomer of Ru(CO) has been prepared and oligomerised by Glaser–Hay coupling to give a cyclic butadiyne-linked trimer. Use of tri(4-pyridyl)triazine as template during the coupling ensured that only a single stereoisomer of the trimer was formed: all three CO groups are forced to be outside the cavity, leaving three potential ruthenium-binding sites facing into the cavity.