Ethyl Bromide → 5-Diethylphosphonomethyl-3-phenylisoxazole

Participants

Reaction Steps

5-Bromomethyl-3-phenylisoxazole (7.14 g, 30 mmol) and triethyl phosphite (10.4 ml, 60 mmol) were heated at 150° C. until no more ethyl bromide distilled, then the temperature maintained for a further 1 h. The mixture was then distilled under reduced pressure to give 5-diethylphosphonomethyl-3-phenylisoxazole bp 190°-192° C. at 0.5 mm Hg (8.15 g, 27.6 mmol, 92%); νmax (film) 2980, 2900, 1605, 1580, 1465, 1440, 1410, 1250, 1160, 1020, 970, 770, 690, 670 cm-1 ; δH (CDCl3) 1.30 (6H, t, J 7 Hz, OCH2CH3), 3.45 (1H, d, JH-P 22 Hz, CH2 -P), 4.10 (4H, m, OCH2CH3), 6.55 (1H, d, J 3 Hz, CH-4), 7.40 (3H, m, Ph), 7.65 (2H, m, Ph); δC (CDCl3) 16.3, 16.4 (OCH2CH3), 24.7, 26.9 (CH2 -P), 62.8, 62.9 (OCH2CH3), 101.5, 101.6 (C-4), 126.8 128.9, 130.0 (Ph), 162.8 (C-3), 164.3, 164.4 (C-2).

Provenance & Evidence