3-(2,5,5-Trimethyl-1,3-dioxan-2-yl)thiophene-2-sulfonamide → 3-Acetyl-2-thiophenesulfonamide

Participants

Reaction Steps

The product from Step A (174.05 g, crude) was dissolved in a mixture of THF (1000 mL) and 1N HCl (1000 mL) and heated at reflux temperature for 1.5 hr. The THF was evaporated and the aqueous solution made basic by the addition of a saturated aqueous sodium bicarbonate solution. The mixture was cooled and the precipitate collected by filtration, washed with cold water and dried in vacuo to give the crude product (109.1 g,). Recrystallization from acetonitrile gave the desired product (81.5 g, 79%): mp 193°-196° C.

Provenance & Evidence