Hydrochloric Acid → Methylphenidate

Participants

Reaction Conditions

Reaction Steps

Hydrogen chloride (gas) was passed through a stirred solution of 7-phenyl-1-azabicyclo[4.2.0]octan-8-one with R*R*/S*R* 3.3:1 by GC (2.61 Kg, 13.0 mol) in methanol (13 L) under reflux conditions for 60 hour until TLC indicated that all starting material had been consumed. The mixture was evaporated under reduced pressure. The residue was treated with hot water (8 L) for 0.5 h. The hot mixture was filtered, cooled to 50° C., washed with toluene (2×1.2 L), cooled to the room temperature, basified with sodium carbonate to pH 10-11 and extracted with dichloromethane (3×2.5 L). The combined organic extracts were dried over sodium sulfate, filtered and evaporated under reduced pressure to give 2.33 Kg (76.9%) of methylphenidate with threolerythro 3.5:1 by GC.

Provenance & Evidence