a new bisguanidinium salt as a multifunctional organocatalyst for asymmetric cascade esterification/aza-Michael reaction between 2-hydroxyphenyl-substituted enones and isocyanates is reported. A high level of enantioinduction and excellent isolated yields were achieved under mild reaction conditions. Enantiomerically enriched 1,3-benzoxazin-2-ones were constructed, and a possible catalytic model was
据报道,开发了一种新的双
胍盐作为多功能有机催化剂,用于2-羟基苯基取代的烯酮和
异氰酸酯之间的不对称级联酯化/氮杂-迈克尔反应。在温和的反应条件下,实现了高
水平的对映体诱导和出色的分离产率。构建了对映体富集的1,3-苯并恶嗪-2-酮,并基于机理驱动的实验,提出了可能的催化模型。