Hydrochloric Acid → HCID 66841931, compound

Participants

Reaction Conditions

Reaction Steps

A solution of borane in THF (1 M, 197 mL) was slowly added to (3S,6R)-1-benzyl-3-ethyl-6-methyl-piperazine-2,5-dione (4.9 g, 19.7 mmol) over 15 min under nitrogen. The reaction mixture was then stirred at 70° C. for 72 h. The resulting solution was cooled to 0° C. and MeOH (60 mL) and 5 M hydrochloric acid (16 mL) were slowly added, then the solution was heated at 70° C. with stirring for 2 h. The solvent was removed in vacuo, and the residue was partitioned between water and Et2O. 1 M aqueous NaOH was added to give pH 12 and the product was extracted with EtOAc (3×). The organic phase was dried (MgSO4), filtered and concentrated to give (2R,5S)-1-benzyl-5-ethyl-2-methyl-piperazine (3.5 g) as a yellow liquid. MS: [M+H]+=219.

Provenance & Evidence