Binuclear organometallic compounds. Part IX. Nuclear magnetic double resonance studies of tin-119 chemical shifts in compounds with transition metal-to-tin bonds

Abstract

The magnetic shieldings determined by heteronuclear double resonance are reported for 35 organotin compounds containing transition-metal atoms. Exceptionally low-field chemical shifts in species with light transition-metal atoms were attributed to a large paramagnetic contribution arising from small average excitation energies associated with d_π–d_π bonding. Heavier transition metals increase the tin shielding but there is no apparent correlation with the s-electron density on the tin atom.