Citric Acid → HCID 89646971, compound

Participants

Reaction Conditions

Reaction Steps

A solution of Example 62B (1.52 g, 6.20 mmol), (R)-2-methylpropane-2-sulfinamide (1.127 g, 9.30 mmol), 2-methyltetrahydrofuran (20 mL), and tetraethoxytitanium (5.20 mL, 24.8 mmol) was heated to 70° C. After 3 hours the solution was cooled to −10° C. and sodium borohydride (0.469 g, 12.4 mmol) was added. The mixture was warmed to room temperature, stirred for 2 hours then cooled to 0° C. and 10% aqueous citric acid (50 mL) was added. The mixture was stirred vigorously overnight then diluted with methyltetrahydrofuran (300 mL). The layers were separated and the organic extract was washed with water and brine, dried (Na2SO4), filtered, and concentrated. Purification by flash chromatography (SiO2, 20-100% hexane/ethyl acetate gradient) provided the title compound (2.14 g, 6.11 mmol, 99% yield). MS (DCI+) m/z 349 (M+H)+.

Provenance & Evidence