Cycloaddition in Synthesis of Sulfonamide Derivatives. IV. One-Pot Synthesis of 3-Dimethylamino-4,1,2-benzoxathiazine 1,1-Dioxides, 3-Methoxy-4-methyl-1,2,4-benzothiadiazine 1,1-Dioxide and 3-Dimethylamino-1,4,2-benzodithiazine 1,1-Dioxides.
作者:Tsuneo IWAKAWA、Hiroto TAMURA、Akira MURABAYASHI、Yoshio HAYASE
DOI:10.1248/cpb.39.1939
日期:——
A novel, one-pot synthesis of 3-dimethylamino-4, 1, 2-benzoxathiazine 1, 1-dioxides (7), 3-methoxy-4-methyl-1, 2, 4-benzothiadiazine 1, 1-dioxide (9) and 3-dimethylamino-1, 4, 2-benzodithiazine 1, 1-dioxides (11) is described. The procedure in the case of 7 involves [2+2] cycloaddition reaction of chlorosulfonyl isocyanate (CSI) with thiocarbamates with subsequent loss of carbonyl sulfide, followed by cyclization of the resulting N-chlorosulfonyl isothioureas under Friedel-Crafts conditions. Synthesis of 9 was achieved similarly. Also, by using dithiocarbamates instead of thiocarbamates, the 1, 4, 2-benzodithiazines 11 were synthesized.
描述了一种新颖的一锅法合成3-二甲氨基-4, 1, 2-苯并噻唑啉-1, 1-二氧化物(7)、3-甲氧基-4-甲基-1, 2, 4-苯并噻二氮杂烯-1, 1-二氧化物(9)和3-二甲氨基-1, 4, 2-苯并二噻唑-1, 1-二氧化物(11)。在7的合成过程中,涉及氯磺酰异氰酸酯(CSI)与硫羧氨基酸的[2+2]环加成反应,随后失去硫酰羰酸,最后在弗里德尔-克拉夫特条件下对得到的N-氯磺酰异硫脲进行环化。9的合成也以类似方式实现。同时,使用二硫羧氨基酸替代硫羧氨基酸合成了1, 4, 2-苯并二噻唑(11)。