L-glufosinate synthesis process and key intermediates

Make Virtual Participation of 2021 China Pesticide Exporting Workshop to see all the presentation video

Due to the price rise of glyphosate and the supply side complications and the impact of the epidemic situation, the price of glufosinate technical soared in 2020, which began to rise at an accelerated rate since this June. The price has hit a new high in five years, with the latest price being quoted at RMB 400,000 per ton.

Glufosinate has two optical isomers: L-isomer and D-isomer, of which, L-isomer is of high efficiency while D-isomer is inactive. L-glufosinate can convert the ineffective D-isomer into effective L-isomer, thus, the amount of use of L-glufosinate per mu (15 mu = a hectare) is reduced by 50%, which leads to reduced cost of production and application in favor of manufacturers and farmers. In addition, L-glufosinate is more environment friendly, which falls in line with the national strategy of reduction of the use of pesticides and increase of the efficiency of pesticide application. Hence, L-glufosinate has become a new focus of market competition.

The synthesis of L-glufosinate is not easy. At present, there are reportedly three synthesis methods of L-glufosinate - asymmetric synthesis, resolution and conversion. So far, only a few domestic enterprises have a good command of the technology of synthesis of L-glyphosate.

At the recent 2021 China Pesticide Exporting Workshop, Cheng Jingshun, the chief engineer of Huimeng Bio-Tech, gave a presentation entitled Synthetic Technology and Application of Glufosinate-ammonium and its Intermediates. In his presentation, Mr. Cheng elaborated on the following process of synthesis of L-glufosinate, having made an analysis of merit and demerit as well as problems of each of the synthesis process: 

• Raceme separation (enzymic resolution and chemical resolution): inclusive of parenzyme resolution and quinine resolution. 

• Chiral adjuvant: inclusive of adjuvant (S)-2-hydroxyl-3-pinone induced synthesis and adjuvant D-valine L-valine methyl ester induced synthesis

• Asymmetric catalysis: inclusive of asymmetric hydrogenation, asymmetric Strecker, asymmetric Michael addition reaction, asymmetric enzyme catalysis, chiral material synthesis …

Mr. Cheng also gave a briefing of the process of synthesis of key intermediates of L-glufosinate, involving L-homoserine and Methyldiethoxyphosphine.

The L-glufosinate synthesis process of Huimeng Bio-Tech is as follows:

The L-homoserine synthesis process of Huimeng Bio-Tech is as follows:

The Methyldiethoxyphosphine synthesis process of Huimeng Bio-Tech is as follows:

If you have more questions regarding synthesis technologies of L-glufosinate, please leave your questions under the presentation video page and interact with the expert Cheng Jingshun.

About Huimeng:  

Huimeng Bio-tech is a biotechnology enterprise integrated of research, development, production and sales of high-tech products, such as pesticide pharmaceutical intermediates, biological fermentation chiral compounds, technicals and technical. We are headquartered in Heze, Shandong Province, with a total asset of 1.236 billion yuan, a total area of 360,000 square meters, and nearly 750 employees nationwide. We have three production bases in Shandong, Anhui and Heilongjiang, respectively, and two R&D centers in Suzhou and Shandong. Huimeng Bio-tech is the first enterprise in China to realize the large-scale production of DCTF (2, 3-dichloro-5-trifluoromethyl pyridine) which was awarded the title of "Single Champion Product" by the Ministry of Industry and Information Technology on December 21, 2020.