Acetic Acid → 3,4,5-Trimethyl-piperazine-1-carboxylic acid benzyl ester

Participants

Reaction Steps

Benzyl 3,5-dimethylpiperazine-1-carboxylate (1 eq, 2.04 mmol, 0.5 g) and formaldehyde (37% in H2O, 5 eq, 10.07 mmol, 0.277 ml) are dissolved in MeOH (10 ml). After 10 mins at room temperature, acetic acid (5 eq, 10.07 mmol, 0.576 ml) and sodium triacetoxyborohydride (5 eq, 10.07 mmol, 2.13 g) are added and the reaction mixture stirred overnight. The reaction is quenched with 5M HCl (15 ml) and the solvent evaporated under vacuo. The residue is taken to pH 13 by addition of sodium hydroxide (4M) and extracted with EtOAc. This organic portion is washed with water and brine, dried over MgSO4, filtered and concentrated in vacuo to afford the title compound.

Provenance & Evidence