Dichloromethane → Di[(2E,4E,6E,8E)-3,7-dimethyl-9-(2,6,6-trimethyl-1-cyclohexenyl)-2,4,6,8-nonatetraenyl](2S)-2-[(tert-butoxycarbonyl)amino]butanedioate

Participants

Reaction Conditions

Reaction Steps

N-Boc aspartic acid (1.2 mg), methylene chloride 20 ml and minimum amount of dimethylformamide (DMF) were added to nitrogen filled, three mouth- round bottom flask and melted. The reaction mixture was cooled down into 0° C., 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride [EDCI](1.36 g)were added slowly, and stirred for approximately 30 minutes. Retinol (0.51 g) was added into the reaction mixture, small amount of N,N′-dimethylaminopyridine (DMAP) were added immediately, and stirred for approximately 1˜3 hours. After the reaction was finished, eluent were removed under the low pressure, the residues were melted with ethyl acetate and washed several times with water and Brine. Organic phase were dried with anhydrous MgSO4, concentrated under low pressure and separated with column chromatography.

Provenance & Evidence