The syntheses of R3Sn-Mn(CO)sub(5-n)Lsub(n)(n=0 or 1) compounds and their 119Sn-Moessbauer and 1H-NMR studies

Seven new compounds with the Sn-Mn bond have been prepared by carbonyl displacement with a weaker π-accepting ligand, L (L=P(C6H5)3, As(C6H5)3, Sb(C6H5)3 for R3Sn-Mn(CO)5) or by reaction of the anion [Mn(CO)5]- or [Mn(CO)4P(C6H5)3]- with R3SnX (R=C2H5, n-C3H7, n-C4H9). A transconfiguration is deduced for the mono-substituted compounds, R3Sn-Mn(CO)4L, on the basis of the infrared spectra in the ν(CO) region. The 119Sn-Moessbauer and IR spectra are measured for sixteen compouns of the R3Sn-Mn(CO)sub(5-n)Lsub(n) type (R=CH3, C2H5, n-C3H7, n-C4H9, Cl, Br, I; L=P(C6H5)3, As(C6H5)3, Sb(C6H5)3; n=0 or 1). Both the Moessbauer-isomer shift and the quadrupole splitting increase with an increase in the length of the alkyl chain attached to the tin atom. The replacement of CO on the manganese atom with the weaker π-accepting ligand, L, has a significant effect on the isomer shift and quadrupole splitting of the tin atom through the sigma-and π-interaction between the tin and manganese atoms. An interpretation of the change in the chemical shift of the terminal methyl protons is also given for alkyl derivatives. (author)