Quadrupole-dipole effects in solid-state, CP-MAS, tin-119 NMR spectra of para-substituted Triaryltin(pentacarbonyl)manganese(I) complexes
Solid-state, CP-MAS, 119Sn NMR spectra were measured for a series of para-substituted triaryltin(pentacarbonyl)manganese(I) complexes. All the spectra show an asymmetric sextet due to spin-spin coupling and second-order quadrupolar effects, transmitted by dipolar coupling between the 119Sn and 55Mn nuclei, which are not suppressed by magic-angle rotation. The solid-state 1JMn-Sn spin-spin and nuclear quadrupole coupling constants range from 130 to 250 Hz and -8 to 21 MHz, respectively, and show an inverse linear correlation, which is attributed to the dominance of the Fermi contact contribution to the 1JMn-Sn coupling. The tris(p-methylthiophenyl)tin derivative is an exception, attributed to a difference in crystal structure from the other complexes. The magnitudes of the principal elements of the 119Sn chemical shift tensors were determined and appear to be strongly influenced by the ring torsion angles and the para-substituents of the phenyl rings. Solid-state 119Sn NMR spectroscopy provides a useful method of probing the electronic environment around the tin and manganese nuclei in transition metal complexes. Copyright 1998 Academic Press.
Christendat
D
Department of Chemistry, McGill University, 801 Sherbrooke St. West, Montreal, Quebec, H3A 2K6, Canada.
Wharf
I
Morin
FG
Butler
IS
Gilson
DFR