Sodium borohydride → HCID 21883638, compound

Participants

Reaction Steps

To a chilled (ice bath), stirred solution of 6-formyl-2-(trifluoromethyl)-2H-1-benzopyran-3-carboxylic acid (Example 75, Step 2) (0.133 g, 0.489 mmol) in THF (1 mL) and ethanol (1 mL) in a 10 mL round bottom flask was added NaBH4 (0.020 g, 0.528 mmol) in two portions. The reaction was allowed to warm to room temperature and more NaBH4 (0.050 g, 1.322 mmol) was added. The total reaction time was 3 hours. The reaction was quenched with aqueous HCl (1 N solution) and was extracted with chloroform. The organic phase was dried over MgSO4, filtered and concentrated in vacuo yielding a foam. This crude product was purified by flash chromatography (silica gel 60, eluant 1:1, hexane-ethyl Acetate with 2% acetic acid). The product collected from the chromatography was recrystallized from hexanes and ethyl acetate, and collected by vacuum filtration yielding the title compound (0.042 g, 31%) as a very pale yellow powder: mp 177.5–180.8° C. 1H NMR (acetone-d6/300 MHz) 7.89 (s, 1H), 7.44 (s, 1H), 7.41 (d, 1H, J=8.3 Hz), 6.99 (d, 1H, J=8.3 Hz), 5.80 (q, 1H, J=7.3 Hz), 4.59 (s, 2H). FABLRMS m/z 275 (M+H). EIHRMS m/z 274.0417 (M+, Calc'd 274.0453). Anal. Calc'd for C12H9F3O4: C, 52.57; H, 3.31. Found: C, 52.43; H, 3.34.

Provenance & Evidence