Acetic Acid → 2-Methylenetetralin-1-one

Participants

Reaction Conditions

Reaction Steps

A 100-ml pressure-proof glass reaction vessel was charged with 2.92 g (0.02 mole) of 1-tetralone, 2.59 g (0.02 mole) of di-n-butylamine, 1.20 g (0.02 mole) of acetic acid and 15 ml of toluene. To the mixture 0.974 g (0.012 mole) of an 37% aqueous formaldehyde solution was added and the vessel was sealed and heated up to 90° C. After maintaining the temperature at 90° C. for 30 minutes, the vessel was cooled to room temperature. The contents were separated by addition of 5 ml of water, and the water layer was washed off with a 50% aqueous acetic acid solution. The toluene layer was further washed with a 10% aqueous hydrochloric acid, saturated aqueous NaHCO3 solution and saturated aqueous sodium chloride solution, to give a solution of 2-methylene-1-tetralone in toluene. The reaction mixture was analyzed by GLC and its composition was found to be 1.45 g of 2-methylene-1-tetralone and 1.16 g of unreacted 1-tetralone (the conversion of 1-tetralone: 60.2%; selectivity: 82.1%).

Provenance & Evidence