Iodobenzene-Catalyzed Preparation of 3,4-Dihydro-1<i>H</i>-2,1-benzothiazine 2,2-Dioxides from 2-Aryl-<i>N</i>-methoxyethanesulfonamides with <i>m</i>-Chloroperoxybenzoic Acid
作者:Hideo Togo、Atsushi Moroda
DOI:10.1055/s-2008-1042945
日期:2008.4
Iodobenzene-catalyzed cyclization of 2-aryl-N-methoxyethanesulfonamides with m-chloroperoxybenzoic acid results in the corresponding 1-methoxy-3,4-dihydro-1H-2,1-benzothiazine 2,2-dioxides in moderate to good yields. In this reaction, reactive hypervalent iodine [(hydroxy)(tosyloxy)iodo]benzene, formed in situ, reacts with the 2-aryl-N-methoxyethanesulfonamides in an electrophilic manner at the aromatic ring to give the corresponding 1-methoxy-3,4-dihydro-1H-2,1-benzothiazine 2,2-dioxides.
在碘苯催化下,2-芳基-N-甲氧基乙烷磺酰胺与间氯过氧苯甲酸发生环化反应,生成相应的 1-甲氧基-3,4-二氢-1H-2,1-苯并噻嗪 2,2-二氧杂化物,收率中等至良好。在该反应中,原位形成的活性高价碘[(羟基)(对甲苯磺酰氧基)碘]苯与 2-芳基-N-甲氧基乙烷磺酰胺在芳香环上发生亲电反应,生成相应的 1-甲氧基-3,4-二氢-1H-2,1-苯并噻嗪 2,2-二氧化物。