Treatment of 4-chloro-5H-1,2,3-dithiazol-5-one with primary and secondary alkylamines (>2 equiv.) in CH2Cl2 at rt afforded symmetrical N,N′-disubstituted ureas in moderate to good yields. Similarly, the reactions with amino acid ester hydrochlorides in the presence of Et3N (>3 equiv.) under the same conditions gave symmetrical ureas.
在室温下,在CH 2 Cl 2中用伯和仲烷基胺(> 2当量)处理4-
氯-5 H -1,2,3-二
噻唑-5-酮,得到对称的N,N'-二取代
脲良品率高。类似地,在相同条件下,在Et 3 N(> 3当量)存在下,与
氨基酸盐酸盐的反应生成对称的
脲。