The Reactivity and Electronic Structure of Benzophenothiazones and Benzophenoxazones

在N，N-二甲基甲酰胺(DMF)中，研究了5H-苯并[a]吩噻嗪-5-酮及其环取代衍生物在滴汞电极上的极谱行为。每个复式洞穴都有明确的两个还原波，其半波电位与Hammett取代基常数&lt；sigma_p&gt；对于母体化合物5H-苯并[a]吩噻嗪-5-酮，通过假定母体化合物与其二阴离子之间的歧化反应，解释了在混合溶剂DMF-甲基纤维素溶液中得到的结果与蒽醌的行为相似。以~3H-吩噻嗪-3-酮或5H-苯并[a]吩噻嗪-5-酮与1，3-碘-5，5-二甲基海因在温和条件下反应，合成了4-碘-~3H-吩噻嗪-3-酮和6-碘-5H-苯并[a]吩噻嗪-5-酮。通过取代的1，4-萘醌与2-氨基苯硫酚在吡啶中的缩合反应，合成了几种取代的6-苯胺基-5H-苯并[a]吩嗪-5-酮衍生物。并对产物的还原和乙酰化反应进行了研究。通过5-取代-2缩合制备了1-substituted-5H-benzo[2，3-a]phenothiazin-5-one，4-substituted-5H-benzo-[6，5-a]phenothiazin-5-one和6-substituted-benzo[a][1，4]benzothiazino[3，2-c]-phenothiazine衍生物，将2-氨基-3-羟基-吡啶分别与5-取代-2，3-二卤代-1，4-萘醌和6，7-二溴-5，8-喹啉不等酮缩合，合成了1，6-二取代-1，6-二取代-1，4-萘醌和2-氨基硫酚-2，6-二取代-2-羟基-2，3-二卤代-1，4-萘醌和4，6-disubstituted-11-aza-5H-benzo[a]phenoxazin-5-one以及6-substituted-11-aza-5H-pyrido[a]phenoxazin-5-one衍生物。得到的化合物经过还原、乙酰化、脱卤化和与苯胺的反应。邻氨基苯酚与5-取代-2，3-二氯-1，4-萘醌缩合得到1-和4-取代-5H-苯并[a]-吩恶嗪-5-酮。

The polarographic behavior of 5H-benzo[a]phenothiazin-5-ones and its ring-substituted derivatives at a dropping mercury electrode was studied in N,N-dimethylformamide(DMF). Each compound cave well-defined two reduction waves, the half-wave potentials of which lineary corrlated with the Hammett substituent constant <sigma_p> . For the parent compound, 5H-benzo[a]phenothiazin-5-one, the similarity with the behavior of anthraquinone, the results obtained in a mixed solvent, DMF-methylcellosolve, were explained by assuming a disproportionation reaction between the parent compound and its dianion.The iodination of quinone imines were performed in acetone. 4-Iodo-3H-phenothiazin-3-one and 6-Iodo-5H-benzo[a]phenothiazin-5-one were prepared by reacting 3H-phenothiazin-3-one or 5H-benzo[a]phenothiazin-5-one with 1,3-Iodo-5, 5-dimethylhydantoin under mild condition. Several substituted 6-anilino-5H-benzo[a]phenothazin-5-one derivatives were prepared by condensation of substituted 1,4-naphthoquinones with 2-aminobenzenethiol in pyridine. The reduction and acetylation of the resulting compounds were also investigated. The 1-substituted-5H-benzo[2,3-a]phenothiazin-5-one, 4-substituted-5H-benzo-[6,5-a]phenothiazin-5-one and 6-substituted-benzo[a][1,4]benzothiazino[3,2-c]-phenothiazine derivatives were prepared by the condensation of 5-substituted-2, 3-dichloro-1,4-naphthoquinones with 2-aminothiophenol.The 1,6-disubstituted- and 4,6-disubstituted-11-aza-5H-benzo[a]phenoxazin-5-one as well as 6-substituted-11-aza-5H-pyrido[a]phenoxazin-5-one derivatives were preparedby condensation of 2-amino-3-hydroxy-pyridine with 5-substituted-2, 3-dichalogeno-1,4-naphthoquinones and 6,7-dibromo-5,8-quinolinequinone respectively. The resulting compounds were subjected to reduction, acetylation, dehalogenation and reaction with aniline. The 1- and 4-substituted-5H-benzo[a]-phenoxazin-5-ones were prepared by the condensation of o-aminophenol with 5-substituted-2, 3-dichloro-1,4-naphthoquinones.