A novel photoisomerzation of 1,2-benzothiazine 1,1-dioxides to 1,3-benzothiazine 1,1-dioxides

被引:9
作者
Elghamry, Ibrahim [1 ]
Doepp, Dietrich [1 ]
Henkel, Gerald [1 ]
机构
[1] Univ Duisburg Essen, Inst Chem, D-47048 Duisburg, Germany
关键词
PIROXICAM-INDUCED PHOTOSENSITIVITY; PHOTOCHEMICAL RING-EXPANSION; PHOTOISOMERIZATION; ISOMERIZATION; DERIVATIVES; MECHANISM; SACCHARIN; ENIGMA;
D O I
10.1002/jhet.5570440416
中图分类号
O62 [有机化学];
学科分类号
070303 ; 081704 ;
摘要
A novel facile photoconversion of 4-hydroxy-1,2-bezothiazine 1,1-dioxides (3a-e) into 4-oxo-1,3-2H-benzothiazine 1,1-dioxides (4a-e) and 4-hydroxy-2-methyl-N-(pyridin-2-yl)-2H-1,2-benzothiazine-3-carboxamide 1,1-dioxide (PRX) into N-methyl saccharin (2) upon 254 nm irradiation in methanol or acetonitrile is reported. The structures of the products have been elucidated by spectroscopic methods and single crystal X-ray structure determination for 4a and 4d.
引用
收藏
页码:849 / 852
页数:4
相关论文
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