Piperidine → 1-Phenyl-2-(piperidin-1-yl)ethane-1,2-dione

Participants

Reaction Steps

Methyl phenylglyoxylate (12.50 Kg, 76.1 mol, 1 eq) was added dropwise to a stirred mixture of piperidine (19.45 Kg, 228 mol, 3 eq) and methanol (5.0 L) for 3.5 hours to maintain the temperature at 45–55° C. The mixture was stirred at the same temperature for 0.5 hour and kept overnight at +4° C. The precipitated solid was filtered off, washed on the filter with cold methanol (5 L) and dried under reduced pressure to a constant weight to give 15.90 kg (96%) of 1-(phenylglyoxylyl)piperidine with 99.9% purity by GC.

Provenance & Evidence