Synthesis of new derivatives of 1-azaphenothiazine (10a-d) via tandem amination methodology is reported. This was achieved by the reaction of 2-aminothiophenol (6) with 2,3,5-trichloropyridine (7) in aqueous basic medium to yield 3-chloro-1-azaphenothiazine (8) as a greenish yellow solid. Compound 8 was then subjected to palladium catalyzed Buchwald-Hartwig coupling reaction with substituted amines (9a-d), by refluxing using palladium acetate [Pd(OAc)2] as palladium source catalyst, potassium carbonate as base, 1,4-bis(2-hydroxy-3,5-ditert-butylbenzyl)piperazine as ligand and tert-butanol (t-BuOH) as solvent at 110 °C to yield 3-anilino-1-azaphenothiazine derivatives (10a-d) in good to excellent yield. The compounds were characterised using UV, FTIR, 1H NMR, 13C NMR spectroscopy and elemental analysis.
报道了通过串
联胺化方法合成新型1-氮杂苯
噻嗪衍
生物(10a-d)。此反应是通过在
水性碱性介质中将2-
氨基
噻吩醇(6)与2,3,5-三
氯吡啶(7)反应,得到3-
氯-1-氮杂苯
噻嗪(8),其为绿色黄色固体。化合物8随后在使用
乙酸钯[Pd(OAc)2]作为
钯源催化剂、
碳酸钾作为碱、1,4-双(2-羟基-3,5-二
叔丁基苯基)
哌嗪作为
配体和
叔丁醇(t-BuOH)作为溶剂的条件下,于110°C回流,进行
钯催化的Buchwald-Hartwig偶联反应,与取代胺(9a-d)反应,得到了3-
苯胺基-1-氮杂苯
噻嗪衍
生物(10a-d),产率良好至优良。通过UV、FTIR、1H NMR、13C NMR光谱和元素分析对这些化合物进行了表征。