Diethyl tetrahydropyran-4,4-dicarboxylate → Ethyl 4-(hydroxymethyl)oxane-4-carboxylate

Participants

Reaction Conditions

Reaction Steps

A solution of diethyl tetrahydro-4H-pyran-4,4-dicarboxylate, the compound of Formula (7a), (12 Kg) in toluene (104 Kg) was cooled to between -30° C. to -35° C., and diisobutylaluminum hydride (69 Kg) was added at such a rate so as to maintain a reaction temperature of -25° C. After the addition was complete, the temperature was raised to 15° C. over 3 hours, and the reaction stirred until all starting material was consumed. The mixture was then recooled to -15° C. and allowed to stand overnight. The product was partitioned between ethyl acetate (54 Kg), ethanol (48 Kg), and saturated sodium sulfate solution (60 liters), and the mixture stirred overnight at 250C. The precipitated salts were filtered off, washed with tetrahydrofuran, and the filtrate washed with brine and separated. The organic layer was dried over magnesium sulfate and solvent removed under reduced pressure, to give ethyl 4-hydroxymethyltetrahydropyran-4-carboxylate (3.8 Kg), the compound of Formula (8a).

Provenance & Evidence