High‐Resolution Solid‐State MAS13C‐ and 1H‐NMR Spectra of Benzenoid Aromatics Adsorbed on Alumina and Silica: Successful Applications of 1D and 2D Pulse Experiments from Liquid‐State NMR

Abstract

AbstractStrong line‐narrowing effects in solid‐state, magic‐angle‐spinning (MAS) 13C‐ as well as 1H‐NMR spectra of benzenoid aromatics adsorbed at alumina or silica surfAccs indicate high mobility of the organic adsorbates. Even under modest spinning rales (1 kHz), dipolar couplings are sufficiently reduced to allow scalar 13C,1H couplings to be measured. Hetero‐ and homonuclear pulse sequences known from high‐resolution NMR in liquids, like SEFT, J‐RESOLVED, DEPT, COSY, and 13C,1H shift‐correlation experiments are successfully applicable. 13C spin‐lattice relaxation limes are as short as 0.5 s (CH) and 1.1 s (Cq), and T1(1H) values are in the order of 0.3 s.