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[摘要]:An effective route to novel arylsulfonamides, e.g., I, is described. It involves a three-component coupling reaction of an enamine derived from the addn. of primary or secondary amines to acetylenecarboxylates with an arylsulfonyl isocyanate. These arylsulfonamides I display dynamic NMR behavior in soln. A different reactivity pattern was obsd. with Me 3-(diethylamino)acrylate (II), generated in situ from Et2NH and Me propiolate. On reaction with an arylsulfonyl isocyanate, II afforded exclusively the azetidine-2,4-dione (malonimide) derivs., e.g., III, in good yield. These malonimides also show dynamic NMR behavior in soln. because of restricted rotation around the C-N bond resulting from conjugation of the side-chain N-atom with the adjacent a,b-unsatd. carbonyl group. |
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