PROCESS FOR PREPARING 5-CHLORO-2,3-DIHYDRO-1H-INDEN-1-ONE

摘要

A process for making 5-chloro-2, 3-dihydro-1 H-inden-1-one comprising contacting 3-chloro-1-(4-chlorophenyl)-1-propanone with a catalyst selected from sulfuric acid and solid acid catalysts having a silicon to aluminum ratio of 2.0 to 150 the sulfuric acid catalyst being used at a temperature of 90-150oC under conditions wherein a solution of the reactant in an inert solvent is added to the reaction mixture, which mixture comprises any 5 chloro-2, 3-dihydro-1 H-inden-1-one already produced, sulfuric acid, and any 3-chloro-1-(4-chlorophenyl)-1-propanone not yet reacted, at a rate of 0.05-1.0 moles of 3-chloro-1-(4-chlorophenyl)-1-propanone per liter of sulfuric acid per hour, and the solid acid catalyst being used at a temperature of 200-425oC under conditions where the 3-chloro-1-(4-chlorophenyl)-1-propanone is fed to the catalyst at a flow rate of 0.5-10 grams of 3-chloro-1-(4-chlorophenyl)-1-propanone per gram of catalyst per hour.