69516-03-6Relevant articles and documents
Chemoenzymatic synthesis of the chiral herbicide: (S)-metolachlor
Zheng, Liangyu,Zhang, Suoqin,Wang, Fang,Gao, Gui,Cao, Shugui
, p. 1058 - 1063 (2006)
A chemoenzymatic approach for the production of (5)-metolachlor, one of the most widely used herbicides, has been developed. The starting material (S)-N-(2-ethyl-6-methylphenyl)alanine was obtained by the use of lipase-catalyzed hydrolytic kinetic resolution. Under the optimal conditions, the good activity and excellent enantioselectivity of lipase B from Candida antarctica (CAL-B, E > 100) are achieved in diethyl ether - water (15% v/v), which is about 9.7-fold more enantioselective than that in a pure buffered aqueous solution (E = 12.1). After a simple extraction procedure is used to separate the acid product from the remaining ester, the remaining ester is racemized, providing the basis for the continuous resolution process. Then (S)-metolachlor is synthesized by a simple chemical method using the enantiomerically pure (S)-acid.
Optically active N-(1'-methyl-2'-methoxyethyl)-N-chloroacetyl-2-ethyl-6-methylaniline as herbicide
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, (2008/06/13)
The optically active mixture of isomers of aRS,1'S(-)-N-(1'-methyl-2'-methoxyethyl)-N-chloroacetyl-2-ethyl-6-methylaniline has improved action against problem weeds over the racemic mixture of isomers known as "Metolachlor".