Synthesis and electrochemical properties of 3,4,5-tris(chlorophenyl)-1,2-diphosphaferrocenes

Beilstein J Org Chem. 2022 Sep 27:18:1338-1345. doi: 10.3762/bjoc.18.139. eCollection 2022.

Abstract

A novel representative of sodium 3,4,5-triaryl-1,2-diphosphacyclopentadienide containing a chloro substituent in the meta-position of the aryl groups was obtained with a high yield based on the reaction of tributyl(1,2,3-triarylcyclopropenyl)phosphonium bromide and sodium polyphosphides. Further reaction of sodium 3,4,5-tris(3-chlorophenyl)-1,2-diphosphacyclopentadienide with [FeCp(η6-C6H5CH3)][PF6] complex gives a new 3,4,5-tris(3-chlorophenyl)-1,2-diphosphaferrocene. The electrochemical properties of 3,4,5-tris(3-chlorophenyl)-1,2-diphosphaferrocene were studied and compared to 3,4,5-tris(4-chlorophenyl)-1,2-diphosphaferrocene. It was found that the position of the chlorine atom on the aryl fragment has an influence on the reduction potential of 1,2-diphosphaferrocenes, while the oxidation potentials do not change.

Keywords: cyclopropenyl bromide; electrochemical properties; phosphacyclopentadienide anion; phosphaferrocene; phosphonium salt; phosphorus heterocycle.

Grants and funding

This work was supported by the grant of the Russian Science Foundation No. 21-73-10204.