3-(Het)芳基-2-氰基丙-2-烯硫酰胺在温和条件下易于与伯胺和过量甲醛反应,以中等收率得到嘧啶并[6,1- b ] [1,3,5]噻二嗪衍生物。此外,2-氰基-2-环己 叉基乙硫基酰胺以相似的曼尼希 型反应, 得到螺环共轭的嘧啶基-1,3,5-噻二嗪。3,7-二苄基-8-(呋喃-2-基)-3,4,7,8-四氢-2 H ,6 H- 嘧啶基[6,1- b ] [1,3,5]的结构通过X射线衍射分析确定噻二嗪-9-腈。
The Mannich reaction in the synthesis of N,S-containing heterocycles 10. Recyclization of stable cyclic michael adducts, N-methylmorpholinium 6-R-6-hydroxy-1,4,5,6-tetrahydropyridine-2-thiolates, to pyrimido[4,3-b][1,3,5]thiadiazines under conditions of aminomethylation reaction
作者:V. V. Dotsenko、K. A. Frolov、S. G. Krivokolysko、V. P. Litvinov
DOI:10.1007/s11172-009-0199-8
日期:2009.7
6-tetrahydro-pyridine-2-thiolates upon the action of primary amines and HCHO in ethanol undergo recyclization to 3,7-disubstituted 8-aryl-3,4,7,8-tetrahydro-2H,6H-pyrimido[4,3-b][1,3,5]thiadiazine-9-carbonitriles in low yields (5–28%). The latter were also obtained by alternative method, viz., by sequential condensation of cyanothioacetamide with aromatic aldehydes, primary amines, and HCHO.