Multinuclear NMR spectroscopic studies of some organometallic N-substituted anilines

Abstract

Proton, carbon-13, nitrogen-15, fluorine-19, and silicon-29 NMR chemical shifts and coupling constants are reported for nine N-substituted anilines of the type XC 6H 4N(H)Y, where X  H and F, and Y  Si(CH 3) 3, Ge(CH 3) 3, Sn(CH 3) 3, and P(BH 3)(CH 3) 2, and the 15N isotopomer of N-trimethylsilylaniline. Resonances in the natural-abundance carbon-13 NMR spectra for both sets of derivatives are assigned on the basis of additivity relationships, proton-coupled spectra, and relative magnitudes of | J( 31P 13C)| and | J( 19F 13C)| coupling constants where appropriate. Carbon-13 and fluorine-19 chemical shifts, and | 1 J( 13C 1H)| coupling constants indicate that the P(BH 3)(CH 3) 2 group is substantially electron-withdrawing.