Trifluoroacetic acid → 3-(1-adamantyl)4-methoxy-N-(trifluoroacetyl)aniline

Participants

Reaction Conditions

Reaction Steps

11.70 ml (84 mmol) of triethylamine in 10 ml of tetrahydrofuran and 8.70 ml (91 mmol) of ethyl chloroformate in 10 ml of tetrahydrofuran are successively added dropwise to a solution of 20.6 g (70 mmol) of 3-(1-adamantyl)-4-methoxybenzoic acid in 200 ml of tetrahydrofuran at 0° C. The reaction medium is stirred for 40 minutes at 0° C., 6.83 g (105 mmol) of sodium azide, dissolved in 30 ml of water, are then added to this medium and the mixture is left stirring at 0° C. for 2 hours. The reaction medium is poured into ice-cold water, the mixture is extracted with dichloromethane and the organic phase is washed with water, dried over magnesium sulphate and evaporated. The residue is dissolved in 400 ml of dichloromethane, 7.3 ml (0.094 mol) of trifluoroacetic acid are added and the mixture is heated to reflux for 30 hours. The reaction medium is poured into saturated sodium bicarbonate solution and the organic phase is dried over magnesium sulphate and evaporated. The residue is chromatographed on silica with a dichloromethane/hexane (30:70) mixture to yield 14.1 g (57%) of 3-(1-adamantyl)-4-methoxy-N-(trifluoroacetyl)aniline, melting point 166°-167° C.

Provenance & Evidence