Structure of Silylated Sulfonamides; a Silicon-29 Nuclear Magnetic Resonance Investigation
The structures of eighteen silylsulfonamides have been determined by 29Si n.m.r.The chemical shifts of the compounds were compared with those of model compounds.The N-silyl tautomer was the only isomer observed, except in cases where strongly electron-withdrawing groups (e.g.Cl, NMe2) were attached to nitrogen; in such cases the O-silyl tautomer dominates.The results have been rationalised in terms of the effect of substituents on the S-N ?-bond order.An estimate of the hitherto unmeasured S=N molar bond enthalpy as 325 kJ mol-1 was obtained.