Potassium Carbonate → 4-(((2R)-1,4-dibenzyl-2-piperazinyl)methyl)-3,3-dimethyl-2-piperazinone

Participants

Reaction Conditions

Reaction Steps

A 20 ml, microwave vial was charged with ((2R)-1,4-dibenzyl-2-piperazinyl)methyl methanesulfonate (0.817 g, 2.18 mmol, Example 184, Step 1), 3,3-dimethylpiperazin-2-one (0.297 g, 2.32 mmol, ChemBridge, San Diego, Calif.), potassium carbonate (0.910 g, 6.58 mmol) and acetonitrile (10 mL). The vial was sealed and the reaction mixture was stirred at 130° C. for 30 min. The reaction was allowed to cool to room temperature then saturated aqueous NH4Cl/water (1:1) (100 mL) and 10% iPrOH in chloroform (100 mL) were added. The aqueous phase was extracted with 10% iPrOH in chloroform (2×50 mL). The combined organic phases were washed with saturated aqueous NaCl (200 mL), dried over sodium sulfate, filtered and concentrated in vacuo. The crude product was purified by column chromatography (50 g of silica gel, 0 to 10% iPrOH (with 10% NH4OH) in CHCl3) to afford 4-(((2R)-1,4-dibenzyl-2-piperazinyl)methyl)-3,3-dimethyl-2-piperazinone (0.53 g) as a white foam.

Provenance & Evidence