Abstract: The present invention provides a process for the preparation of N-[2,4-dichloro-5-[4-(difluoromethyl)-4,5-dihydro-3-methyl-5-oxo-1H-1,2,4- triazol-1-yl]phenyl]methanesulfonamide (I) which comprises reacting 2-(5-amino-2,4-dichlorophenyl)-4-(difluoromethyl)-2,4-dihydro-5-methyl-3H- 1,2,4-triazol-3-one (II) with methanesulfonyl chloride in the presence of a catalytic amount of a source of soluble halide.

Abstract: A process for preparing 5-chloro-2,3-dihydro-1H-inden-1-one comprising contacting 3-chloro-1-(chlorphenyl)-1-propanone with a catalyst selected from sulfuric acid and solid acid catalysts.

Abstract: A process for the preparation of 2-carboalkoxy-1-indanones of Formula I from 1-indanones of Formula II using a dialkyl carbonate and an alkali metal alkoxide is provided. This process is superior to the prior art in that it avoids pyrophoric reagents such as sodium hydride, and proceeds in high chemical yield and product quality. The invention provides a novel process to an important intermediate in the preparation of arthropodicidal carboxanilides of commercial interest. ##STR1## wherein: R.sup.1, R.sup.2 and M are defined in the specification.