A General and Robust Method for the Preparation of (E)- and (Z)-Stereodefined Fully Substituted Enol Tosylates: Promising Cross-Coupling Partners
作者:Hidefumi Nakatsuji、Yoo Tanabe、Yuichiro Ashida、Yuka Sato、Atsushi Honda
DOI:10.1055/s-0035-1562482
日期:——
preparing (E)- and (Z)-stereodefined fully substituted enol tosylates is described. α-Substituted β-keto esters undergo (E)-selective enol tosylations using TsCl–Me2N(CH2)6NMe2 as the reagent (method A, 13 examples; 63–96%) and (Z)-selective enol tosylations using TsCl–TMEDA–LiCl as the reagent (method B, 13 examples; 62–99%). A plausible mechanism for the (E)- and (Z)-enol tosylation selectivity is proposed
摘要 描述了一种制备(E)-和(Z)-立体定义的完全取代的烯醇甲苯磺酸盐的稳健方法。使用TsCl–Me 2 N(CH 2)6 NMe 2作为试剂,α取代的β-酮酯经历(E)选择性烯醇化(方法A,13例; 63–96%)和(Z)选择性烯醇使用TsCl–TMEDA–LiCl作为试剂进行甲苯磺酰化(方法B,13例; 62–99%)。提出了对于(E)-和(Z)-烯醇甲苯磺酰化选择性的合理机理。阿1 1 H NMR监测实验揭示的TsCl加上TMEDA形成的简单Ñ-磺酰胺基中间体。 描述了一种制备(E)-和(Z)-立体定义的完全取代的烯醇甲苯磺酸盐的稳健方法。使用TsCl–Me 2 N(CH 2)6 NMe 2作为试剂,α取代的β-酮酯经历(E)选择性烯醇化(方法A,13例; 63–96%)和(Z)选择性烯醇使用TsCl–TMEDA–LiCl作为试剂进行甲苯磺酰化(方法B,13例; 62–99%)。提