3-(2-Methylphenyl)propionic acid → 4-Methyl-1-indanone

Participants

Reaction Steps

A solution of 12.0 g (73.2 mmol) of 2-methylbenzenepropanoic acid in 125 ml of methylene chloride was added portion-wise to 500 g of polyphosphoric acid. The mixture was heated for six hours on the steam bath and the resulting orange solution was diluted with 1.5 l of ice. The solid was collected, washed with water, and air dried to give 7.2 g crude material. Recrystallization from ethanol/water gave 5.8 g of the desired product; mp 94°-97°. Extraction of the original diluted reaction mixture with methylene chloride gave an additional lot. Total recovery was 7.7 g (72%).

Provenance & Evidence