Studies of Acyl and Thioacyl Isocyanates. VIII. Cycloaddition Reactions of Benzoyl and Thiobenzoyl Isocyanates with Carbodiimides
作者:Otohiko Tsuge、Kazuko Sakai
DOI:10.1246/bcsj.45.1534
日期:1972.5
The investigations of cycloaddition reactions of benzoyl and thiobenzoyl isocyanates with carbodiimides have shown that the adducts formed from benzoyl isocyanates and N,N′-dicyclohexylcarbodiimide are the corresponding (4+2) cycloadducts, and not the (2+2) cycloadducts proposed by Neidlein. The reaction of isocyanates with N,N′-diphenylcarbodiimide at 0°C gave (2+2) cycloadducts, which were thermally
苯甲酰基和硫代苯甲酰基异氰酸酯与碳二亚胺环加成反应的研究表明,由苯甲酰基异氰酸酯和 N,N'-二环己基碳二亚胺形成的加合物是相应的 (4+2) 环加合物,而不是 Neidlein 提出的 (2+2) 环加合物. 异氰酸酯与 N,N'-二苯基碳二亚胺在 0°C 反应生成 (2+2) 环加合物,然后将其热异构化为相应的 (4+2) 环加合物。苯甲酰基异氰酸酯与 N-环己基-N'-苯基碳二亚胺反应生成异氰酸酯与碳二亚胺中环己基-N=C 键的 (4+2) 环加合物。在用中性氧化铝处理时,(4+2) 环加合物很容易异构化为 1,3,5-三嗪。硫代苯甲酰异氰酸酯与碳二亚胺的两个 N=C 键反应,得到两个异构 (4+2) 环加合物。