PROCESS FOR PREPARING 1,2,3,9-TETRAHYDRO-9-METHYL-3-METHYLENE-4H- CARBAZOL-4-ONE AND ONDANSETRON THEREFROM

摘要

The present invention provides a rapid, high-yielding process for preparing 1,2,3,9-tetrahydro-9-methyl-3-methylene-4H-carbazol-4-one from 1,2,3,9-tetrahydro-9-methyl-4H-carbazol-4-one without using a secondary amine as a catalyst, and without using glacial acetic acid as a solvent. The present invention further provides a rapid, high-yielding process for preparing ondansetron from 1,2,3,9-tetrahydro-9-methyl-3-methylene-4H-carbazol-4-one without using alumina as a catalyst.