Sulfur Dioxide → 3-(2-Hydroxypropyl)thiophene-2-sulfonamide

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-(2-hydroxypropyl)thiophene (2.95 g, 20.77 mmol) in THF (25 mL) at -78° C. was added n-butyllithium (18.3 mL of a 2.5M solution, 45.69 mmol). This mixture was stirred at -78° C. for 1 hr and sulfur dioxide was added until the solution maintained a pH of 3. The reaction mixture was warmed to room temperature, stirred for 30 min, and evaporated to a residue which was dissolved in water (25 mL). Sodium acetate (5.1 g, 62.31 mmol) and hydroxylamine-O-sulfonic acid (7.0 g, 62.31 mmol) were added, the mixture stirred at room temperature for 18 hr, and the pH was adjusted to 8 with sodium bicarbonate. This solution was extracted with ethyl acetate (2×200 mL), the extracts were dried (MgSO4) and evaporated to a residue which was purified by column chromatography (silica, 50% hexane/ethyl acetate) to give 1.9 g (42%) of the desired product.

Provenance & Evidence