Membrane-Based Process for the Synthesis of Chiral Pyrethroids

许多农药是手性的——也就是说，它们的化学结构以一对“手”对映体的形式存在。通常，一对对映体中只有一个表现出所需的生物活性。尽管越来越多的证据表明，关键农药应该以单一对映体的形式开发和销售，但90%以上的合成手性农药是以含有两种对映体的外消旋混合物的形式销售的。主要原因是制备手性农药所需的对映体纯手性中间体成本高，技术难度大。该项目的目标是开发一种简单、经济的方法来制备对映异构纯(s)-m-苯氧苯甲醛氰丙烷，这是一种重要的手性中间体，用于合成拟除虫菊酯杀虫剂——一种重要的商业高效杀虫剂。在第一阶段，我们证明了我们的方法的技术和经济可行性，这是基于双膜酶-反应器工艺。在这个二期项目中，我们计划对该工艺进行表征和优化，并通过一个实验规模装置的建设和运行，与我们可能的三期赞助商（一家间苯氧苯甲醛氰丙烷的主要制造商）产生商业化该工艺所需的数据。

Many pesticides are chiral--that is, their chemical structures exist as a pair of "hand" enantiomers. Generally, only one of the pair of enantiomers exhibits the desired biological activity. Despite mounting evidence that critical pesticides should be developed and marketed as single enantiomers, more than 90% of the synthetic chiral pesticides are marketed as racemic mixtures, which contain both enantiomers. The principal reason is because of the high cost and technical difficulty of preparing the enantiomerically pure chiral intermediates needed to prepare the chiral pesticide. The goal of this program is to develop a simple, cost- effective process to prepare enantiomerically pure (s)-m- phenoxybenzaldehyde cyanohydrin, an important chiral intermediate used in the synthesis of pyrethroid insecticides--a commercially important class of highly effective insecticides. In Phase I, we demonstrated the technical and economic feasibility of our approach, which is based on dual-membranes enzyme-reactor process. In this Phase II program, we plan to characterize and optimize the process and, through construction and operation of a bench-scale unit, generate the data necessary to commercialize the process with our probable Phase III sponsor, a major manufacturer of m-phenoxybenzaldehyde cyanohydrin.