The First High-yielding Benzyne Cyclisation Using a Phenolic Nucleophile: A New Route to Xanthenes
作者:David W. Knight、Paul B. Little
DOI:10.1055/s-1998-1878
日期:1998.10
Condensation of dianion 2 derived from aminobenzotriazole 1 with O-benzyl-salicylaldehydes 11 gives intermediate alcohols 12 in good yields. Double hydrogenolysis gives phenols 13 which, upon deprotection and benzyne generation using N-iodosuccinimide, undergo smooth cyclisation to give the iodo-xanthenes 14 in excellent overall yields.
由氨基苯并三唑 1 衍生出的二元离子 2 与 O-苄基水杨醛 11 缩合,得到中间醇 12,收率很高。双重氢解可得到苯酚 13,苯酚 13 在使用 N-碘代丁二酰亚胺进行脱保护和生成苄后,会发生平滑的环化反应,从而以极佳的总收率得到碘-氧杂蒽 14。