反应详情

A solution of 2.8 g of 5-(3,4-dimethoxyphenyl)-6-ethyl-3,6-dihydro-1,3,4-thiadiazin-2-one ("A") [obtainable by reacting 1-(3,4-dimethoxyphenyl)-2-bromobutan-1-one with methyl hydrazinethioformate] in 150 ml of acetone is boiled with 3 g of 4-nitrobenzyl chloride in the presence of 4 g of potassium carbonate for eight hours. The insoluble residue is filtered off and the solution is concentrated. The residue is worked up in the conventional manner to give 3-(4-nitrobenzyl)-5-(3,4-dimethoxyphenyl)-6-ethyl-3,6-dihydro-1,3,4-thiadiazin-2-one as a colorless oil.

1. filtrationThe insoluble residue is filtered off
2. concentrationthe solution is concentrated