Cycloaddition in synthesis of sulfonamide derivatives. III. Convenient synthesis of 3-alkylthio-4H-1,2,4-benzothiadiazine 1,1-dioxides.
作者:Tsuneo IWAKAWA、Hiroto TAMURA、Yoshio HAYASE
DOI:10.1248/cpb.38.1075
日期:——
Synthesis of 3-alkylthio-4-methyl-4H-1, 2, 4-benzothiadiazine 1, 1-dioxides was conveniently achieved by [2+2] cycloaddition reaction of S-alkyl N-methyl-N-phenyldithiocarbamates with chlorosulfonyl isocyanate with subsequent loss of carbonyl sulfide, followed by cyclization of the resulting chlorosulfonyl isothioureas under Friedel-Crafts conditions.
3-烷基硫代-4-甲基-4H-1, 2, 4-苯并噻二唑-1, 1-二氧化物的合成可通过S-烷基N-甲基-N-苯基二硫氨基甲酸酯与氯磺酰异氰酸酯的[2+2]环加成反应方便地实现,随后失去硫代羰基,接着在Friedel-Crafts条件下对得到的氯磺酰异硫脲进行环化反应。