(S)-6-METHYL-PIPERAZIN-2-ONE synthesis

Yield:323592-68-3 95%

Reaction Conditions:

with hydrogen;palladium 10% on activated carbon in methanol; for 24 h;

Steps:

4

To a solution of methyl N-((2R)-2-{[(benzyloxy)carbonyl]-amino}propyl)glycinate (12.5 g, 44.6 mmol) in anhydrous methanol (446 mL) under an atmosphere of N2 was added 10% Pd/C (1.25 g). The flask was then placed on a Buchi hydrogenator and purged three times with N2 followed by 3 times with H2. The reaction was allowed to stir under hydrogen (2.2 L, 98.12 mmol) until no more hydrogen was consumed. Once complete (24 hours), the reaction mixture was poured through Celite and the filtrate was concentrated. Ethyl acetate (5-10 mL) was added causing a white solid to crash out. This white solid was dried and collected to provide the desired product in 95% yield (4.8 g, 42.37 mmol). (The filtrate can be concentrated and more of the product can be crashed out by addition of ethyl acetate. If any starting material remains, it will be in the filtrate.

References:

WO2004/112793,2004,A1 Location in patent:Page/Page column 119