Sodium Hydroxide → HCID 66714730, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of Intermediate 19A (340 mg, 1.483 mmol) in tetrafluoroboric acid (1 mL, 7.65 mmol) at −10° C. was added sodium nitrite (179 mg, 2.60 mmol) in small portions, keeping the temperature below −5° C. After the addition was complete, the mixture was stirred at 0° C. for 45 min and then warmed slowly to room temperature over a period of 30 min to decompose the preparation of diazonium salt. The temperature of the mixture was rose to 30-35° C. and nitrogen was evolved for about 30 min. The resulting mixture was cooled to −10° C. and neutralized with 1M sodium hydroxide precooled to 0-5° C. The mixture was extracted with ethyl acetate (2×25 mL), washed with cooled water (25 mL), and dried over magnesium sulfate. The crude material was purified by silica gel chromatography (40 g ISCO column, eluting with 100% hexanes to 100% CH2Cl2) to provide Intermediate 19B (60 mg, 0.258 mmol, 17.42% yield) as a yellow solid. MS (ES): m/z=233.0 [M+H]+. 1H NMR (400 MHz, MeOD) δ ppm 2.34 (s, 3 H) 7.44 (dd, J=9.66, 5.65 Hz, 1 H) 7.55 (d, J=8.28 Hz, 1 H) 8.20 (dd, J=8.16, 2.13 Hz, 1 H) 8.28 (d, J=2.26 Hz, 1 H) 8.57 (d, J=9.79 Hz, 1 H) 8.70 (dd, J=7.65, 5.65 Hz, 1 H).

Provenance & Evidence