A Practical Aryl Unit for Azlactone Dynamic Kinetic Resolution: Orthogonally Protected Products and A Ligation-Inspired Coupling Process
作者:Sean Tallon、Francesco Manoni、Stephen J. Connon
DOI:10.1002/anie.201406857
日期:2015.1.12
The first strategy for bringing about enantioselective azlactone dynamic kinetic resolution to generate orthogonally protected amino acids has been developed. In the presence of a C2‐symmetric squaramide‐based catalyst, benzyl alcohol reacts with novel yet readily prepared tetrachloroisopropoxycarbonyl‐substituted azlactones to generate trapped phthalimide products of significant synthetic interest
已经开发出用于产生对映选择性氮杂内酯动态动力学拆分以产生正交保护的氨基酸的第一种策略。在C的存在下2 -对称的基于方酰胺的催化剂,苯甲醇与新型的但易于制备的四氯异丙氧基羰基取代的内酯反应,生成具有重要对映体控制意义的,具有重大合成意义的被困邻苯二甲酰亚胺产品。这些材料是被掩盖的氨基酸,它们被证明是正交保护的:邻苯二甲酰亚胺的裂解可以在酯的存在下实现,反之亦然。该过程可用于使受保护的丝氨酸(以化学计量负载)与衍生自天然和非生物氨基酸的外消旋a内酯进行高度立体选择性的连接型偶联。脱保护后,随后的碱基介导的O→N酰基转移发生,形成二肽。