反应详情

温度

-10 °C

A slurry of 1 (10.97 g, 42.1 mmol) in dry methanol (5 ml) was treated with triethylamine (6.45 ml). After clearing, anhydrous ether (200 ml) was added to the solution and cooled to -10° C. for one hour. Precipitated triethylamine hydrochloride was removed by filtration and the filtrate concentrated to a limpid yellow oil. The oil was added to dry methanol (250 ml) previously saturated with NH3 (g) at -10° C., tightly stoppered and left at -10° C. for 42 hours. The precipitated product was collected and dried under vacuum. The liquid filtrate was spotted on a TLC plate and developed with CHCl3 :MeOH (4:1) which revealed one spot at Rf =0.50, identical to that of the collected precipitate. The filtrate was therefore stripped to dryness and the remaining solid 2 combined with the precipitate (8.12 g, 92.3%): mp 160°-162° C.; 1H NMR (220 MHz, DMSO-d6), δ 8.07 (d, 2, J32 8.0), 7.5 (d, 2, J=8.0), 7.41 (s, 1), 7.00 (s, 1), 3.50 (t, 1, J=6.0), 3.09 (dd, 1, J=6.0, 16.0); 2.81 (dd, 1, J=6.0, 16.0) CI-MS 210 ((M+1)/z).

1. customPrecipitated triethylamine hydrochloride was removed by filtration
2. concentrationthe filtrate concentrated to a limpid yellow oil
3. additionThe oil was added to dry methanol (250 ml) previously saturated with NH3 (g) at -10° C.
4. customThe precipitated product was collected
5. customdried under vacuum