Sodium borohydride → HCID 67439654, compound

Participants

Reaction Steps

A solution of 2-dimethylamino-6-[3-formyl-4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenoxy]-nicotinonitrile (7) (370 mg, 0.94 mmol) in CH2Cl2 (5 mL) was added to a mixture of NaBH4 (26 mg, 0.66 mmol) in anhydrous methanol (10 mL) at room temperature. Additional solid NaBH4 (82 mg, 2.2 mmol) was then added portionwise over a period of 10 minutes. The reaction mixture was then stirred for a further 1 h at room temperature. The reaction was quenched by the addition of a solution of glacial acetic acid (0.2 mL) and distilled water (0.2 mL) followed by stirring for 10 minutes. The reaction was concentrated to give an oil (˜550 mg). The oil was dissolved in a mixture of acetic acid/methanol/CH2Cl2 (1/2/100 v/v/v, 100 mL) followed by the addition of silica gel (5 g, 230-400 mesh) and concentrated to dryness to give a free flowing impregnated silica. This was loaded onto a silica column (10 g, 230-400 mesh) and eluted with acetic acid/methanol/CH2Cl2 (1/2/100 v/v/v). The fractions containing D95 were collected and concentrated to give a light yellow coloured oil. The oil was freeze dried by first diluting with MeOH/CH2Cl2 (1/1 v/v, 15 mL) followed by the addition of deionised water (200 mL), the resultant white suspension was frozen in a dry-ice acetone bath and placed overnight on freeze-dryer. A white solid of D95 was obtained (70 mg, 25% isolated yield). 1H NMR 400 MHz (d6-DMSO) δ 9.23 (s, 1H), 7.95 (d, J=8.6 Hz, 1H), 7.77 (d, J=7.8 Hz, 1H), 7.23 (d, J=0.5 Hz, 1H), 7.16 (dd, J=7.8, 0.5 Hz, 1H), 6.31 (d, J=8.6 Hz, 1H), 4.98 (s, 2H), 3.14 (s, 6H). Mass Spectrum [M+H+]=296. HPLC purity 95.04% (Maxplot), 94.63% (220 nm), 92.41% (254 nm).

Provenance & Evidence