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[摘要]:Hydrolysis of N-(1-dimethylcarbamoyl-1-methylethyl)-thiiranimines occurs with S-C(sp(2)) ring cleavage while attack of hydrochloric acid results in S-C(sp(3)) ring opening. The latter mode of ring opening is also observed in [3+2] cycloaddition reactions with iso(thio)cyanates where the heterocumulene reacts via the C-chalcogen bond; only a sterically less hindered isopropyl substituted thiiranimine adds to the C=N bond in isocyanates to yield 4-thiohydantoins. The cycloadducts give a variety of hydrolysis products, in particular imidazo[2,1-b]oxazoles and -thiazoles, oxazolones, and stable thietes. Insertion of a thiocarbonyl into an isopropyl CH bond is observed yielding an annulated cyclopropane unit. |
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