Acetic Anhydride Generated Imidazolium Ylide in Ring Closures onto Carboxylic Acids; Part of the Synthesis of New Potential Bioreductive Antitumor Agents
作者:Fawaz Aldabbagh、Eamonn Joyce、Patrick McArdle
DOI:10.1055/s-0030-1260543
日期:2011.5
Acetic anhydride behaves as a traceless activating agent allowing thermal intramolecular condensation of 2-(benzimidazol-1-ylmethyl) benzoic and nicotinic acids. Autoxidation gives benzimidazo[1,2-b]isoquinoline-6,11-diones (intermediates characterized) and benzimidazo[2,1-g]-1,7-naphthyridine-5,12-diones in a facile, one-pot transformation. The 1,4-dimethoxy analogue of the former is converted into
乙酸酐充当无痕活化剂,允许 2-(苯并咪唑-1-基甲基)苯甲酸和烟酸进行分子内热缩合。自氧化生成苯并咪唑并[1,2-b]异喹啉-6,11-二酮(中间体表征)和苯并咪唑[2,1-g]-1,7-萘啶-5,12-二酮,简单、一锅法转化. 使用硝酸铈铵 (CAN) 将前者的 1,4-二甲氧基类似物转化为苯并咪唑并[1,2-b]异喹啉-1,4,6,11-四氢呋喃。1,7-萘啶-5,12-二酮体系容易开环,得到甲醇加合物的X射线晶体结构。