Study On The Synthesis Process Of Amide Herbicides Metolachlor

This paper discussed briefly the state and the prospect of metolachlor in the worldwide pesticide market ,introduced metolachlor's physical nature and herbicide performance,determined an industrially feasible route of produing metolachlor, which went through 3steps:l-methoxy-2-propanol as starting material,synthesizing successively its intermediates: methoxyacetone,2-ethyl-6-methyl—(1'-methoxy-2'-propyl)-N-acetanilide and the last is metolachlor. Their structures and purities were confirmed by GC/MS, ~1HNMR, IR. This paper majorly studied the technological optimization process of metolachlor and its intermediates through single factor experiment/uniform test design.The total yield of metolachlor was up to 72.0% under the optimum reaction conditions.The influential factors of synthesizing methoxyacetone were investigated by single factor experiments and uniform test design. The optimum process conditions of the product were obtained by regression analysis ,followed as: reaction temperature 70℃,the value of pH was 4,reaction time 4h.Under the optimum reaction conditions,the yield of methoxyacetone reached 77.9%.The influential factors of synthesizing2-ethyl-6-methyl—(1'-methoxy-2'-propyl)-N-acetanilide were investigated by single factor experiments and uniform test design.The optimum process conditions of the product were obtained by regression analysis, followed as: n(2-methyl-6-ethylaniline):n(methoxyacetone)=1:1.5,reaction pressure is 3.5 Mpa,reaction temperature 40~45 ℃,the quantity of catalyst 0.5g.Under the optimum reaction conditions,the yield of metolachlor reached 96.6% .The influential factors of synthesizing metolachlor were investigated by single factor experiments and uniform test design. The optimum process conditongs of the product were obtained by regression analysis ,followed as :...