Tert-Butyl nitrite → HCID 69001380, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-amino-4-(3-bromo-4,5-dimethoxy-phenyl)-3-cyano-4H-indolo[4,5-b]pyran (0.998 g, 2.34 mmol) in anhydrous THF (40 mL) kept at −30° C., was added tert-butylnitrite (1.0 mL, 7.58 mmol) via a syringe under argon. The light yellow solution was stirred between −20 to −10° C. for 4 h, then allowed to warm up to 0° C. The reaction mixture was cooled to −10° C. and sodium borohydride (NaBH4, 0.259 g, 6.84 mmol) was added in one portion. The reaction mixture was warmed up to room temperature slowly and stirred overnight (15 h). The THF solvent was evaporated and the residue was dissolved in EtOAc (100 mL). The mixture was washed with saturated NaHCO3 (15 mL) and brine (15 mL), dried over MgSO4, and evaporated to yield a brown residue. The residue was purified by flash column chromatography (silica gel, EtOAc:hexanes/1:2) to yield 0.390 g (40%) of the product as an off-white solid. 1H NMR (CDCl3): 8.30 (brs, 1H), 7.45 (d, J=0.6 Hz, 1H), 7.24 (t, J=2.7 Hz, 1H), 7.13 (dd, J=0.8, 8.6 Hz, 1H), 6.96 (d, J=2.1 Hz, 1H), 6.76 (d, J=1.8 Hz, 1H), 6.70 (J=8.1 Hz, 1H), 6.67 (m, 1H), 4.81 (s, 1H), 3.84 (s, 3H), 3.83 (s, 3H).

Provenance & Evidence