Organocatalytic Asymmetric Conjugate Additions to Cyclopent‐1‐enecarbaldehyde: A Critical Assessment of Organocatalytic Approaches towards the Telaprevir Bicyclic Core
作者:Luca Bernardi、Mariafrancesca Fochi、Riccardo Carbone、Ada Martinelli、Martin E. Fox、Christopher J. Cobley、Bhaskar Kandagatla、Srinivas Oruganti、Vilas H. Dahanukar、Armando Carlone
DOI:10.1002/chem.201503352
日期:2015.12.21
In the context of a programme directed at the manufacture of telaprevir, eight possible approaches to its bicyclic α‐amino acid core, based on organocatalytic enantioselective conjugate additions to cyclopent‐1‐enecarbaldehyde, were identified and preliminarily explored. Four reactions, delivering advanced intermediates en route to the target amino acid, were selected for a thorough optimisation. Three
在针对telaprevir的生产计划的背景下,基于对环戊-1-烯甲醛的有机催化对映选择性共轭加成反应,确定并初步探索了八种可能的双环α-氨基酸核心途径。为了全面优化,选择了四个反应,这些反应在向目标氨基酸的途中提供了先进的中间体。此反应中的三个涉及用脯氨醇催化剂(添加硝基甲烷,硝基乙酸盐和乙酰氨基丙酸盐)进行亚胺离子催化,一个基于金鸡纳衍生的相转移催化剂(添加甘氨酸亚胺)。在某些情况下,精心选择添加剂可将催化剂负载量降低至0.5 mol%。通过利用现成的底物和催化剂,制备能够以高收率和对映选择性接近特拉匹韦的核心的中间体,突显了有机催化技术在经济高效地制备药物方面的潜力。