The reaction of 5, 6-dihydrothiazolo [2, 3-b] thiazolium salt (1) with the sodium salt of acetylacetone furnished 3-(2-thiazolyl)-acetylacetone (2) with elimination of thiirane and 2-acetonylidene-3-acetylthioethyl-4-thiazoline (3). The reaction of 1 with the sodium salt of ethyl acetoacetate gave ethyl 2-(2-thiazolyl)-acetoacetate (12) and the reaction of 1 with the sodium salts of ethyl cyanoacetate and malononitrile gave 2-substituted thiazole (16), 3-(2-mercaptoethyl)-thiazoline (17) and/or its disulfide (18). The tautomeric forms of 2, 12 and 16 are discussed on the basis of the structures of the methylated products and of their spectrophotometric properties.
5,6-二氢
噻唑并[2,3-b]
噻唑盐(1)与
乙酰乙酸钠反应,生成3-(2-
噻唑基)
乙酰乙酸(2),同时脱去
硫杂
环丙烷和2-
丙酮亚甲基-3-乙酰
硫乙基-4-
噻唑啉(3)。1与
乙酰乙酸乙酯钠盐反应得到乙基2-(2-
噻唑基)
乙酰乙酸酯(12),而1与
氰乙酸乙酯钠盐和
丙二腈钠盐反应则生成2-取代
噻唑(16)、3-(2-巯基乙基)
噻唑啉(17)及其二
硫化物(18)。根据甲基化产物的结构及其分光光度特性,讨论了2、12和16的互变异构形式。