p-Toluenesulfonic acid → HCID 18942876, compound

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Reaction Steps

Four hundred mg of p-toluenesulfonic acid dissolved in 25 ml of methanol was added, with stirring, to the 3-pivaloyloxybenzaldehyde of Example I. Trimethylorthoformate (224 ml; 2.05 mol) was then added dropwise. The minor exotherm that resulted was allowed to proceed unchecked while the mixture was stirred for 1 hour. One half gram of sodium bicarbonate was added, and the flask was placed on the rotary evaporator (bath temperature40° C.) to remove all volatiles. The resulting oil was passed through a short silica gel column under nitrogen pressure to give an orange-brown oil which was pumped under vacuum (1.0 mm Hg) with stirring to yield 426 g of crude 3-pivaloyloxybenzaldehyde dimethyl acetal. Infrared analysis revealed no aldehyde carbonyl absorption (1695 cm-1).

Provenance & Evidence