Sodium Hydroxide → HCID 57446949, compound

Participants

Reaction Steps

To a suspension of N-acetyl-5,5,5-trifluoroleucine (4.2 g, 18.5 mmol) in H2O (35 mL) was added 1 M aqueous NaOH (18.5 mL, 18.5 mmol) and the mixture was stirred for 15 to 30 min to give a homogenous solution. Acylase I (EC 3.5.1.14, from Sigma, Cat. # A 3010; 55 mg) was added and the mixture was stirred at room temperature overnight. Crude NMR of a small aliquot (evaporated under vacuum) showed a ratio of 53:47 for starting material and product. The mixture was then acidified with 6M aqueous HCl (Q3.5 mL) and extracted with EtOAc (4×, each EtOAc extraction was washed with a small amount of H2O). The combined EtOAc extracts were washed with brine, dried (MgSO4) and concentrated to afford the crude N-acetyl-5,5,5-trifluoro-D-leucine as a pale yellow solid, [α]D=+27.60 (c 1.5, EtOH). The aqueous layer was concentrated under vacuum and dried under vacuum overnight to afford 5,5,5-trifluoro-L-leucine, probably contaminated with NaCl and HCl salts, [α]D=−1-4.1° (c 0.77, H2O).

Provenance & Evidence