Fast DKR of Amines Using Isopropyl 2-Methoxyacetate as Acyl Donor
作者:Martijn A. J. Veld、Karl Hult、Anja R. A. Palmans、E. W. Meijer
DOI:10.1002/ejoc.200700568
日期:2007.11
The dynamic kinetic resolution (DKR) of various primary amine substrates was performed using a modified version of the Backvall system. A single equivalent of isopropyl2-methoxyacetate was used as acyldonor in combination with p-MeO Shvo complex as the racemization catalyst and Novozym 435 as the acylation catalyst. A reaction temperature of 100 °C was employed to ensure a high racemization rate
各种伯胺底物的动态动力学拆分 (DKR) 使用 Backvall 系统的改进版本进行。使用一当量的 2-甲氧基乙酸异丙酯作为酰基供体,结合 p-MeO Shvo 配合物作为外消旋化催化剂和 Novozym 435 作为酰化催化剂。采用 100 °C 的反应温度以确保高外消旋化速率。添加浓度为 0.5 M 的 2,4-二甲基-3-戊醇 (DMP) 作为氢供体成功地抑制了副产物的形成。在这些改进的 DKR 条件下,大多数底物在 26 小时内观察到完全转化,显示出高 ee 值和良好的化学选择性,而原始系统需要 72 小时的反应时间。
PROCESS FOR THE PRODUCTION OF ALIPHATIC ISOCYANATES
申请人:Daussin Rory D.
公开号:US20110275854A1
公开(公告)日:2011-11-10
The present invention is a process for aliphatic or cycloaliphatic isocyanate. The process comprises reacting an aliphatic or cycloaliphatic primary amine, with phosgene in the presence of an inert solvent wherein the initial reaction temperature is between 100 and 130° C. and the temperature is subsequently ramped to 150 to 180° C. during the course of the reaction, the solvent to amine weight ratio is 95:5 to 80:20, the total reaction pressure is maintained between 50 and 350 psig and the amine is rapidly dispersed in the phosgene through injection in a region of high efficiency mixing.