Ethylene Glycol → Benzyl 1,4-dioxa-7-azaspiro[4.4]nonane-7-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of benzyl 3-oxopyrrolidine-1-carboxylate (2.00 g), ethane-1,2-diol (2.85 mL), p-toluenesulfonic acid monohydrate (10 mg) and toluene (20 mL) was stirred with heating in a Dean-Stark apparatus at 120° C. for 6 hr. The mixture was allowed to cool to room temperature, diluted with ethyl acetate (10 mL), washed successively with water (5 mL×2) and brine (5 mL), and dried over anhydrous sodium sulfate. Insoluble material was removed by filtration, and the filtrate was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate/hexane) to give the title compound (2.1 g) as a pale-yellow liquid.

Provenance & Evidence