Toluene → 2,2,4,6,7-Pentamethyl-3-(4-methylphenyl)-2,3-dihydro-1-benzofuran-5-amine

Participants

Reaction Conditions

Reaction Steps

To a mixture of N-benzyl-2,2,4,6,7-pentamethyl-3-(4-methylphenyl)-2,3-dihydro-1-benzofuran-5-amine (80 g), toluene (240 mL) and isopropanol (80 mL) was added 10% Pd-carbon (a product containing 50% water, 4 g), and the mixture was hydrogenated at 35° C. under atmospheric pressure. After completion of the reaction, the catalyst was filtered. Concentrated hydrochloric acid (19.2 mL) was added to the filtrate and the mixture was stirred at 10° C. or below for 1 hour. Precipitated crystals were filtered. The crystals were added to a mixture of methanol (560 mL) and water (80 mL) and the mixture was heated to 50° C. to dissolve the crystals. Then, 25% aqueous ammonia water was added dropwise to the solution to adjust to pH 8.5. Precipitated crystals were filtered to obtain the title compound (54.32 g, 88.6%).

Provenance & Evidence