Triethylamine → HCID 69110241, compound

Participants

Reaction Steps

A mixture of crude 1-amino-4,4-diphenylcyclohexane-1-carboxylic acid (510 mg, 1.73 mmole), triethylamine (0.37 ml, 2.65 mmole), 9-fluorenylmethyl succinimidyl carbonate (Fmoc-OSu, 880 mg, 2.61 mmole) in acetonitrile (25 ml) and water (25 ml) was stirred at room temperature overnight. TLC analysis of the reaction indicated the presence of starting material amino acid. 9-fluorenylmethyl succinimidyl carbonate (200 mg) and acetonitrile (5 ml) were added and the mixture was stirred at room temperature for another 24 hours. The reaction mixture was concentrated in vacuo to remove most of the acetonitrile, acidified to pH 3 with 10% aqueous citric acid solution, and the white emulsion extracted three times with ethyl acetate. The combined organic layers were washed with water, brine, dried over sodium sulfate. Filtration and concentration gave a crude oil which was purified by column chromatography (eluted with 1→4→8% methanol/methylene chloride) to give Fmoc-1-amino-4,4-diphenylcyclohexane-1-carboxylic acid (350 mg, 39% yield) as a white solid. HRMS (FAB): C34H32NO4 (M+H) calc. 518.2331; observed: 518.231

Provenance & Evidence