The Synthesis of 2-Cyano-cyanothioformanilides from 2-(4-Chloro-5H-1,2,3-dithiazol-5-ylideneamino)benzonitriles Using DBU
作者:Panayiotis Koutentis、Sophia Michaelidou
DOI:10.1055/s-0029-1217059
日期:——
A series of 2-(4-chloro-5H-1,2,3-dithiazol-5-ylideneamino)benzonitriles were prepared from the reaction of 4,5-dichloro-1,2,3-dithiazolium chloride (Appel salt) and the corresponding anthranilonitriles. Reaction of the 1,2,3-dithiazolimines with DBU (3 equiv) at -5 ËC gave the corresponding 2-cyano-cyanothioformanilides in near quantitative yields. Treatment of 2-(4-chloro-5H-1,2,3-dithiazol-5-ylideneamino)benzonitrile with DBU (4 equiv) at -5 to +20 ËC gave 2-isothiocyanatobenzonitrile in 96% yield. The latter compound was also formed directly from 2-cyano-cyanothioformanilide on treatment with DBU (1 equiv) in 95% yield. A tentative mechanism for the DBU-mediated dithiazole to cyanothioformanilide transformation is proposed and all compounds were fully characterized.
一系列2-(4-氯-5H-1,2,3-二噻唑-5-亚氨基)苯腈是通过4,5-二氯-1,2,3-二噻唑铵氯化物(阿佩尔盐)与相应的氨基苯腈反应制备的。1,2,3-二噻唑亚胺与DBU(3当量)在-5°C反应后得到相应的2-氰基-氰基硫甲酰胺,收率接近定量。将2-(4-氯-5H-1,2,3-二噻唑-5-亚氨基)苯腈与DBU(4当量)在-5至+20°C反应后得到的2-异硫氰酸苯腈的收率为96%。该化合物也可以通过将2-氰基-氰基硫甲酰胺与DBU(1当量)反应直接生成,收率为95%。提出了DBU介导的二噻唑转化为氰基硫甲酰胺的初步机制,并对所有化合物进行了充分表征。