Polyfunctional heteroaromatics: a route to dicyanomethylene thiazoles based on the reaction of α-thiocyanatoketones with malononitrile
作者:Saleh Mohammed Al-Mousawi、Moustafa Sherief Moustafa、Mohamed Hilmy Elnagdi
DOI:10.3998/ark.5550190.0011.217
日期:——
Reactions of α-S-cyanothioketones 6a-c with malononitrile were observed to form 2-(thiazol- 2(3H)-ylidene)malononitrile derivatives 7a-c. The thiazole products readily react with aromatic diazonium salts to yield 2-(5-phenylazo-3H-thiazol-2-ylidene)-malononitrile derivatives 8a-c. The malononitrile derivative 8c undergoes a condensation with DMF/DMA to yield thiazolo(5,4- c)pyridazine 12. Reactions
观察到 α-S-氰基硫酮 6a-c 与丙二腈的反应形成 2-(噻唑-2(3H)-亚基)丙二腈衍生物 7a-c。噻唑产物容易与芳族重氮盐反应以产生 2-(5-苯基偶氮-3H-噻唑-2-亚基)-丙二腈衍生物 8a-c。丙二腈衍生物 8c 与 DMF/DMA 缩合生成噻唑并(5,4-c)哒嗪 12。7a-c 与水合肼反应生成二氨基吡唑 9a-c,后者与烯胺酮 13 反应生成相应的噻唑基吡唑并 (1,5-a) 嘧啶 14。此外,丙二腈衍生物 8a 与重氮苯氯化物反应容易得到偶联产物 10。