Tetrabutylammonium Fluoride → 2-Tert-butyl-5-(3-hydroxy-phenyl)-1,1-dioxo-1,2-dihydro-1lambda6-isothiazol-3-one

Participants

Reaction Conditions

Reaction Steps

A solution of 4.08-A (1.39 g, 3.5 mmol) in tetrahydrofuran (14 mL) at 0° C. was treated with tetra-n-butylammonium fluoride (1.1 g, 4.2 mmol) dropwise. The reaction mixture was stirred at 25° C. for 30 min and diluted with ethyl acetate (150 mL) and washed with 0.1 N HCl (100 mL) and brine (50 mL). The organic layer was dried with Na2SO4, filtered, and concentrated to give a crude residue which was purified using flash column chromatography (100% hexane to 30% ethyl acetate/hexane) to yield 4.08-B as a white solid (0.95 g, 96%). 1H NMR (500 MHz, CDCl3): δ 7.39 (dd, J=7.8, 7.8 Hz, 1H), 7.34–7.32 (m, 1H), 7.26–7.24 (m, 1H), 7.05–7.02 (m, 1H), 6.63 (s, 1H), 5.3 (br s, 1H), 1.73 (s, 9H); LCMS found for C13H16NO4S (M+H)+: m/z=282.

Provenance & Evidence