Formaldehyde → HCID 57095110, compound

Participants

Reaction Conditions

Reaction Steps

The 4-benzylamino-5-hydroxy-2,6,6-trimethyl-2-cyclohepten-1-one obtained in Example 1 (5.86 g, 21.5 millimoles) was dissolved in formic acid (30 ml), formalin (30 ml) was added, and the mixture was heated at 90° C. for 3 hours. The reaction solution was concentrated and alkalified with a 1% aqueous sodium hydroxide solution. The aqueous solution was subjected to extraction with benzene, washed with water, and then dried over anhydrous potassium carbonate. The benzene solution was concentrated, and the resulting residue was subjected to silica gel column chromatography with hexane-ethyl acetate (9:1) as the eluent, to obtain 2.95 g of crude product which was then recrystallized from hexane to give 2.39 g (39%) of 5-hydroxy-4-(N-methylbenzylamino)-2,6,6-trimethyl-2-cyclohepten-1-one as colorless crystals. Melting point: 78.5°~80° C.

Provenance & Evidence