N-(TERT-BUTOXYCARBONYL)-3,3,3-TRIFLUOROALANINE synthesis

Yield:188030-43-5 90%

Reaction Conditions:

Stage #1: 3,3,3-trifluoro-DL-alaninewith tetramethyl ammoniumhydroxide in acetonitrile; for 0.5 h;
Stage #2: di-tert-butyl dicarbonate in acetonitrile; for 2.5 h;

Steps:

7.B7 Example 7; B7; 2-[(tert-butoxycarbonyl)amino]-2-(trifluoromethyl)acetic acid

To a 50 mL round bottom flask was added DL-3,3,3-Trifluoro-2-alanine (419.8 mg, 2.93 mmol), tetramethylammonium hydroxide (1.10 g, 6.05 mmol) and acetonitrile (20 mL). The reaction was allowed to stir until the mixture turned clear (approx. 30 minutes). To the solution was added (Boc)2O (1.35 mL, 5.87 mmol) and the clear solution was allowed to stir for 2.5 hours. The reaction was concentrated, and the residue was diluted with diethyl ether. The aqueous phase was extracted with diethyl ether and acidified with 10% HCI. The aqueous phase was extracted with ethyl acetate and the combined organic layers were washed with brine, dried over magnesium sulphate, filtered and concentrated to yield the title compound as a white solid (644.0 mg, 90%).

References:

WO2004/22534,2004,A1 Location in patent:Page 44