1033548-25-2Relevant articles and documents
Synthesis of diazaheterocyclic ring-fused 1,2,4-benzothiadiazine 1,1-dioxides by a sequential aza-Wittig/NH-addition cyclization/nucleophilic ring-closure methodology with N-alkenyl-2-carbodiimidobenzenesulfonamides as key intermediates
Hirota, Shinsuke,Kato, Ryo,Suzuki, Madoka,Soneta, Yuji,Otani, Takashi,Saito, Takao
scheme or table, p. 2075 - 2083 (2009/04/04)
Treatment of N-alkenyl-2-azidobenzenesulfonamides with triphenylphosphane and subsequent subjection of the resulting 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 dioxides. In one case a methanobridged benzothiatriazabicyclotridecanone was obtained. The scope and limitations of these cyclizations are reported. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.