The reaction of a carbamoylsilane with nitrone was described. α-(N’-methyl-N’-trimethylsiloxylamino)-N,N-dimethylphenylacetamide was synthesized and its tautomeric structures were studied. The evidence for the assigned structures was provided by 1H NMR (temperature changed from 55 ℃ to －30 ℃). It can be seen from 1H NMR data that there are two representative tautomeric structures——structure (5) at 55 ℃ and structure (8) at －30 ℃, and there are different intermediate structures at different temperatures between 55 ℃ and －30 ℃.

Key words: carbamoylsilane, nitrone, tautomerism