Reduction Behavior of Anisyl-substituted P-Ferrocenyl Phospholes

Chempluschem. 2023 Jun;88(6):e202300143. doi: 10.1002/cplu.202300143.

Abstract

P-Ferrocenylphospholes with differing substituents in α-position have been synthesized and their identity and purity was confirmed using multinuclear NMR spectroscopy, MS, elemental analysis and single crystal X-ray diffraction. Furthermore, the redox properties have been explored with electrochemical measurements. Transferring the reduction to a preparative scale using lithium leads to reductive P-C bond cleavage furnishing the corresponding phospholide which has been transformed to P-tert-butyl substituted phosphole. In addition to phospholide formation reductive demethoxylation with transformation of the anisyl substituent to its phenyl analog was observed. For comparison analogous reactions have been explored for the respective P-phenylphospholes which show a different reactivity.

Keywords: electrochemistry; ferrocene; heterocycle; phosphorus; reduction.