(2S)-2-(((tert-butoxy)carbonyl)amino)-3-cyclohexylpropanoic acid → (S)-(-)-2-(tert-Butoxycarbonylamino)-3-cyclohexyl-1-propanol

Participants

Reaction Steps

To a solution of (2S)-2-[(tert-butoxycarbonyl)amino]-3-cyclohexylpropanoic acid (5.0 g, 18 mmol) in tetrahydrofuran (50 mL) at 0° C. was added 1.0 M borane-THF complex in THF (55.3 mL, 55.3 mmol). After addition, the reaction mixture was stirred at room temperature for 3 hours, then cooled down with an ice-bath, and quenched by the slow addition of AcOH:MeOH (1:5, 40 mL). Then the mixture was 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: 168.1 (M−Boc)+.

Provenance & Evidence