Visible-light photolysis of [FeCp(η6-toluene)][PF6] as a clean, convenient and general route to iron-vinylidene and iron-acetylide complexes

Visible-light photolysis of the cheap starting material [FeCp(η6-toluene)][PF6] (Cpη5-C5H5) using a simple 100-W globe in the presence of diphenyldiphosphinoethane (dppe) and terminal alkynes cleanly yields the vinylidene complexes [FeCp(dppe)(CCHR)][PF6] and, upon further deprotonation, the iron-alkynyl complexes; the reaction is extended to ferrocenylacetylene to yield a bimetallic complex.

Graphical abstractIron-vinylidene (and subsequently iron-acetylide) complexes are easily and quantitatively synthesized by photolysis of the sandwich complex [FeCp(η6-toluene)][PF6] using visible light in the presence of a terminal alkyne. The reaction is general and extended to the synthesis of bimetallic complexes.Figure optionsDownload full-size imageDownload as PowerPoint slide