反应详情

温度

80 °C

To a solution of the compound of example 54 (6.13 g, 39.8 mmoles) in 20% aqueous acetic acid (57 ml) was added dropwise a solution of NaNO2 (3.29 g) in water (13 ml) at 80° C. A pink precipitate was formed which was stirred at 80° C. for an additional 2 hours. The reaction mixture was cooled down in the refrigerator overnight and the resulting precipitate was filtered off, yielding the title compound as a pink powder (4.98 g, yield 68%). Spectral data are identical with those described e.g. by W. Pfleiderer et al. in Chem. Ber. (1961) 94, 12.

1. customA pink precipitate was formed which
2. temperatureThe reaction mixture was cooled down in the refrigerator overnight
3. filtrationthe resulting precipitate was filtered off