Sodium borohydride → ethyl 8-(hydroxymethyl)-6-methyl-2-(trifluoromethyl)-2H-chromene-3-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

The ethyl 8-formyl-6-methyl-2-(trifluoromethyl)-2H-chromene-3-carboxylate from Example 605a, Step 1 (0.32 g, 1.02 mmole) was dissolved in a mixture of THF (1.5 mL) and ethanol (1.5 mL) and the solution was chilled to 0° C. (ice bath). Sodium borohydride (0.04 g, 1.02 mmole) was added portionwise to the above solution and the mixture was allowed to stir for 1 hour. The reaction was quenched with 0.5N HCl (5 mL) and extracted with CH2Cl2 (2×10 mL). The combined extracts were washed with brine (20 mL), dried over MgSO4, filtered and concentrated in vacuo to give a yellow oil (0.3 g, 93%): GCMS m/z 316.0 (M+). 1H NMR (CDCl3/400 MHz) 7.78 (s, 1H), 7.11 (s, 1H), 6.96 (s, 1H), 5.71 (q, 1H, J=7.0 Hz), 4.67 (m, 2H), 4.30 (m, 2H), 2.27 (s, 3H), 1.33 (m, 3H).

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