Stereochemistry and absolute signs of 3JP–H nuclear spin coupling constants in methyl platinum(II) complexes containing tertiary phosphines

Abstract

Absolute signs for ³J_P–H nuclear spin coupling constants of the methyl protons in some methylplatinum(II) tertiary phosphine complexes are positive for phosphorus atoms cis to the methyl group and negative for a phosphorus atom trans to methyl. Negative signs have been found for the coupling of platinum to methyl protons, ²J_Pt–H in these complexes and to olefin protons in dimethyl-[2-vinylphenyl(diphenyl)phosphine]platinum(II). The geminal olefin protons in this compound have a positive-signed coupling with phosphorus. Platinum and phosphorus chemical shifts and coupling constants obtained from INDOR spectra are reported.