432 mg of (R)-I-[(10-chloro-4-oxo-3-phenyl-4H-benzo[a]quinolizin-1-yl)carbonyl]-2-pyrrolidinemethanol and 4 mg of tetrabutylammonium iodide in 2 ml of methylene chloride were held in an ultrasound bath for 30 minutes with 104 mg of sodium hydroxide in 0.1 ml of water. 0.19 ml of dimethyl sulfate was then added. After about 1 hour, an additional 0.19 ml of dimethyl sulfate was added and the mixture was allowed to react for an additional 90 minutes. The mixture was diluted with methylene chloride, washed with water, dried over sodium sulfate, filtered and evaporated. The residue was chromatographed on silica gel and the product was recrystallized from cyclohexane/ethanol. There was obtained (R)-1-[(10-chloro-4-oxo-3-phenyl-4H -benzo[a]quinolizin-1-yl)carbonyl]-2-methoxymethylpyrrolidine as yellow crystals of m.p. 137°-140°.
