Hydrochloric Acid → 2,7-Dioxaspiro[3.5]nonan-1-one

Participants

Reaction Conditions

Reaction Steps

To a mixture of 4-hydroxymethyl-tetrahydropyran-4-carboxylic acid (3.84 Kg), 4-dimethylaminopyridine (0.6 Kg) in dichloromethane (32 liters) was added triethylamine (4.88 Kg). The mixture was cooled to -20° C., and a solution of benzenesulfonyl chloride (4.66 Kg) in dichloromethane (5 liters) was added over a period of 35 minutes, maintaining the temperature below -10° C. The mixture was stirred at -10° C. for 30 minutes, then 3N hydrochloric acid (10 liters) and water (10 liters) were added with stirring, then the layers allowed to separate. The organic layer was separated, the aqueous layer washed with dichloromethane (16 liters), the combined organics washed with aqueous 5% sodium bicarbonate solution (12 liters), then with water (12 liters), and solvent removed under reduced pressure, to give 2,7-dioxaspiro[3,5]nonane-1-one, a compound of Formula (10a)

Provenance & Evidence