Yield:-

Reaction Conditions:

with triethylamine in dichloromethane;

Steps:

19

1-Boc-2(S)-ethyl-5(R)-methylpiperazine acetic acid salt (10 g) was dissolved in dichloromethane (100 mL) and treated with triethylamine (4 nriL, 3 g). Solvent was evaporated and the residue was passed through a silica gel column, eluting with 3% methanol (containing ammonia) in dichloromethane, to give 1-Boc-2(S)-ethyl-5(R)-methylpiperazine free base (7.2 g).

References:

WO2006/91428,2006,A2 Location in patent:Page/Page column 121