Synthesis of Diazaheterocyclic Ring-Fused 1,2,4-Benzothiadiazine 1,1-Dioxides by a Sequential Aza-Wittig/NH-Addition Cyclization/Nucleophilic Ring-Closure Methodology withN-Alkenyl-2-carbodiimidobenzenesulfonamides as Key Intermediates
作者:Shinsuke Hirota、Ryo Kato、Madoka Suzuki、Yuji Soneta、Takashi Otani、Takao Saito
DOI:10.1002/ejoc.200701131
日期:2008.4
iminophosphoranes to aza-Wittig reactions with isocyanates generated functionalized carbodiimides, which spontaneously underwent cyclization to form 2-alkenyl-3-(R2-substituted amino)-2H-1,2,4-benzothiadiazine 1,1-dioxides by internal nucleophilic addition. Subsequent (tandem) cyclizations through iodoamination or hydroamination with HgII/NaBH4 produced a variety of diazaheterocyclic ring-fused benzothiadiazine
用三苯基膦处理 N-烯基-2-叠氮基苯磺酰胺,随后将所得亚氨基膦与异氰酸酯进行氮杂-维蒂希反应,生成官能化碳二亚胺,其自发进行环化形成 2-烯基-3-(R2-取代氨基)-2H- 1,2,4-苯并噻二嗪 1,1-二氧化物通过内部亲核加成。随后通过碘胺化或加氢胺化与 HgII/NaBH4 进行(串联)环化产生了多种二氮杂杂环稠合苯并噻二嗪二氧化物。在一种情况下,获得了甲烷桥连的苯并硫杂三氮杂双环十三酮。报告了这些环化的范围和局限性。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)