The reaction of 5, 6-dihydrothiazolo [2, 3-b] thiazolium salts (1) with hydroxide ion furnished disulfide of 3-(2-mercaptoethyl)-4-thiazolin-2-one (6). The reaction of 1 with hydrogensulfide ion furnished 3-(2-mercaptoethyl)-4-thiazolin-2-thione (7) and/or its disulfide (8) and with N, N-dimethyldithiocarbamate ion furnished 3-(N, N-dimethyl-dithiocarbamylethyl)-4-thiazolin-2-thione (12) whereas the reaction of 1b with thiophenolate ion afforded 3-(2-phenylthioethyl)-4-thiazolin-2-thione (18b), thiazole (21), 6b, phenyl 2-[2-(4-phenylthiazolin-2-thion-3-yl) ethylthio] ethyl disulfide (22) and phenyl 2-phenylthioethyl disulfide (23). Brief reaction mechanism of the formation of these products are discussed. The reaction of 1 is considered to be initiated by the attack of the nucleophile on the polarized >C=N< bond to form an adduct and to proceed through AE-mechanism. The elimination stage of the reaction is concluded to depend upon basicity, polarizability and other properties of the reagent to induce either the cleavage of S7-C7a bond, the cleavage of S7-C7a and N-C5 bonds, or another attack of the reagent on C5 or on S7.
5, 6-二氢
噻唑并[2, 3-b]
噻唑鎓盐(1)与氢氧根离子反应得到3-(2-巯基乙基)-
4-噻唑啉-2-酮(6)的二
硫化物。 1与
硫氢离子反应得到3-(2-巯基乙基)-4-
噻唑啉-2-
硫酮(7)和/或其二
硫化物(8),与N,N-
二甲基二硫代
氨基甲酸根离子反应得到3-(N,N-)二甲基-二
硫代
氨基甲酰乙基)-4-
噻唑啉-2-
硫酮(12),而1b与
苯硫酚根离子的反应得到3-(2-苯
硫基乙基)-4-
噻唑啉-2-
硫酮(18b)、
噻唑(21)、6b、苯基2-[2-(
4-苯基噻唑啉-2-
硫磷-3-基)乙
硫基]乙基二
硫醚(22)和苯基2-苯
硫基乙基二
硫醚(23)。讨论了这些产物形成的简要反应机理。 1的反应被认为是由亲核试剂攻击极化的>C=N<键形成加合物并通过AE机制进行的。反应的消除阶段取决于试剂的碱性、极化性和其他性质,以诱导 S7-C7a 键的裂解、S7-C7a 和 N-C5 键的裂解,或试剂对C5 或 S7。