Influence of a dimetal ion binding ferrocene ligand on the samarium diiodide promoted pinacol coupling reaction

Abstract

Substantial yield increases have been noted in the use of a di-SmI₂ binding ligand for the pinacol coupling of alkyl aldehydes compared to 1∶1 complexes of SmI₂ and tetraglyme. High diastereoselectivities of ca. 10∶1 are also observed for α-substituted alkyl aldehydes in favour of the (±)-isomers.