(S)-2-((tert-Butoxycarbonyl)amino)-3-cyclopropylpropanoic acid → (S)-tert-Butyl 1-cyclopropyl-3-hydroxypropan-2-ylcarbamate

Participants

Reaction Steps

To a solution of (2S)-2-[(tert-butoxycarbonyl)amino]-3-cyclopropylpropanoic acid (2.5 g, 11 mmol) in tetrahydrofuran (30 mL) at 0° C. was added 1.0 M borane-THF complex in THF (32.4 mL). After addition, the reaction mixture was stirred at room temperature for 3 hours, then cooled down with an ice-bath, quenched by the slow addition of AcOH:MeOH (1:5, 20 mL) and the mixture was then warmed to room temperature for 2 hours. The THF volume was reduced by ½ and the product was partitioned between saturated aqueous NaHCO3 and DCM. The combined organic fractions were dried over Na2SO4 and concentrated under reduced pressure to give an oil residue, which was used directly in the next reaction without further purification. LC-MS found: 216.1 (M+H)+.

Provenance & Evidence