Abstract: The present disclosure provides a new and improved process for preparation of intermediate compounds and synthesis of mesotrione therefrom. The present disclosure provides an economical, efficient and eco-friendly process for preparation of mesotrione.

Abstract: The present disclosure provides process for preparation of azimsulfuron or its salts, isomers, and other derivatives thereof. The process involves treating a compound of formula I, with aqueous acetic acid or formic acid and chlorine gas or sodium hypochlorite in presence of hydrochloric acid in chlorinated solvents such as dichloromethane, 1,2-dichloroethane or with aqueous acetic acid and N-chlorosuccinimide or hydrogen peroxide in presence of hydrochloric acid in aqueous cyclic ether such as tetrahydrofuran, 1,4-dioxane to obtain 1-methyl-4-(2-methyl-2H-tetrazol-5-yl)-1H-pyrazole-5-sulfonyl chloride; converting the sulfonyl chloride to a sulfonamide and treating the sulfonamide with a phenyl(4,6-dimethoxypyrimidin-2-yl) carbamate to obtain azimsulfuron or its salts, isomers, and other derivatives thereof.