The reactions of N-monosubstitued thioureas (1) with β-haloacyl halides (2) were carried out in 5% NaOH–CH2Cl2 in the presence of a phase transfer catalyst to afford N-thioamido-β-lactams (3 and 5), thioureido acids (4), and 5-hydroxy-2-thiohexahydropyrimidin-4-ones (6). The compounds, 3 and 4, were readily converted to 5,5-dimethyl-2-thiohexahydropyrimidin-4-ones (7) with 6N HC1.
N-单取代
硫脲(1)与β-卤代
酰卤(2)的反应在5% NaOH–
CH2Cl2中的相转移催化剂存在下进行,生成N-
硫酰基-β-内酰胺(3和5)、
硫脲酸(4)和5-羟基-2-
硫六氢
嘧啶-4-酮(6)。化合物3和4可以用6N HCl方便地转化为5,5-二甲基-2-
硫六氢
嘧啶-4-酮(7)。