Aminoisobutyric acid → Ammonium Hydroxide

Participants

Reaction Steps

To a stirred solution of (±)-tert-butyl [1-(3,5-difluorophenyl)-1-methyl-2-oxoethyl]carbamate (4.00 g, 14.0 mmol, described in U.S. Patent Application Publication No. US 2007/0265225) and 2-methylalanine (4.34 g, 42.1 mmol) in AcOH (25 mL) was added sodium triacetoxyborohydride (3.57 g, 16.8 mmol). The reaction mixture was stirred for 24 h, with additional sodium triacetoxyborohydride (1.00 g) added at 16 and 20 h. The reaction mixture was diluted with water (75 mL) and extracted with CH2Cl2 (4×50 mL). The combined organic extracts were dried over Na2SO4, filtered, and concentrated in vacuo. The crude product was purified by silica gel chromatography, eluting with a gradient of CH2Cl2:MeOH:NH4OH—97:3:1 to 85:15:1, to give the title compound. MS: m/z=373 (M+1).

Provenance & Evidence