The first efficient method for the intramolecular trapping of benzynes by phenols: a new approach to xanthenes
作者:David W. Knight、Paul B. Little
DOI:10.1039/b103834f
日期:——
-1H-benzotriazole and silyloxysalicylaldehydes 10 give excellent yields of the expected adducts 11. While attempts to remove the N-Boc function were unsuccessful, desilylation and hydrogenolysis delivered the hydroxybenzyl derivative 14 which could be efficiently deprotected to give the amine 15. This then underwent smooth decomposition to the benzyne 16, upon exposure to N-iodosuccinimide, and intramolecular
二价阴离子1之间的冷凝源于1-(N-丁氧基羰基氨基)-1 H-苯并三唑和甲硅烷氧基水杨醛10给出预期的加合物11的优良产率。虽然尝试去除N -Boc功能没有成功,但是去甲硅烷基化和氢解作用可释放出羟基苄基衍生物14,该羟基苄基衍生物14可以被有效地脱保护而得到N- Boc功能。胺 15。然后顺利进行分解 到 苯并 16,暴露于N-碘琥珀酰亚胺,并通过苯酚基团与碘的分子内捕获,以得到碘氧杂蒽17。一种更有效的方案是将二价阴离子1 与2-(苄氧基)芳基醛缩合; 初始产物19和22a的氢解作用都可以使氢的脱保护苯酚的功能并影响苯甲醇基团的氢解。最终的酸性脱保护并暴露于N-碘琥珀酰亚胺碘蒽酮21和23的收率很高,首次证明了一种可行的分子内诱捕方法。苯并 通过酚基。