Simple Generation of Ester-Stabilized Azomethine Ylides from 2-Amino Esters and Carbonyl Compounds. Stereochemistry of Their Cycloadditions
作者:Otohiko Tsuge、Shuji Kanemasa、Masayuki Ohe、Kiyotaka Yorozu、Shigeori Takenaka、Kazunori Ueno
DOI:10.1246/bcsj.60.4067
日期:1987.11
esters with carbonyl compounds leads to simple generation of ester-stabilized azomethine ylides which are trapped by olefinic dipolarophiles as cycloadducts. Anti ylides are exclusively involved in the cycloadditions when N-substituted 2-amino esters are employed for the ylide generation, while syn ylides from N-unsubstituted 2-amino esters. Relative stability among all possible ylide isomers has been
2-氨基酯与羰基化合物的缩合导致简单生成酯稳定的偶氮甲碱叶立德,其被烯属偶极亲和物捕获为环加合物。当 N-取代的 2-氨基酯用于叶立德生成时,反叶立德仅参与环加成反应,而 N-未取代的 2-氨基酯产生的顺叶立德。已经检查了所有可能的叶立德异构体之间的相对稳定性,并基于 1,5-偶极相互作用或氢键稳定性解释了特定叶立德形式的选择性参与。还讨论了环加成的内选择性和外选择性。