119Sn-Mössbauer and 1H- and 55Mn-NMR Spectroscopic Studies of a Series of Compounds, R3−xXxSn-Mn(CO)5

The electronic configuration around the tin atom for a series of organotin-manganese compounds, R3−xXxSn–Mn(CO)5, has been studied by 119Sn-Mössbauer and 1H- and 55Mn-NMR spectroscopies. All the results obtained from these spectroscopic measurements show that the Mn(CO)5 group is a stronger electron donor than the methyl, phenyl, or halogen group and that the tin-manganese bond prefers the sσ-character whereas the tin-halogen bond prefers the pσ-character. The relationship between the 55Mn-chemical shift and the 119Sn-isomer shift indicates some σ-electron withdrawal from manganese to tin. The phenyl group reduces the magnitude of quadrupole splitting more than the methyl group; this fact may be due to the mesomeric effect of the phenyl group through the π-bond between tin and ligand atoms. The relationship among the 119Sn-isomer shift, the 1H-chemical shift, and the coupling constant J(119Sn-1H(CH3)) is also shown.