反应详情

温度

150 °C

A round bottom flask is charged with 38 g (0.12 mole) of 2-(p-methoxyphenyl)-6-bromomethyl-benzoxazole (compound of the formula (221)) in 38 ml of triethylphosphite and the reaction mixture is heated to 150° C., kept for 30 minutes at this temperature and then excess triethylphosphite is distilled off in vacuo (10 mm). The residue, a brown oil, congeals after 10 hours. The crude product (44.5 g =98.9% of theory) is stirred with hexane in a mixer. The fine crystalline suspension is filtered by suction and the filter cake is washed with hexane, affording 40 g (88.9% of theory) of 6-(diethylphosphonomethyl)-2-(p-methoxyphenyl)-benzoxazole of the formula ##STR63## in the form of light beige-coloured crystals with a melting point of 86°-88° C.

1. distillationexcess triethylphosphite is distilled off in vacuo (10 mm)
2. waitThe residue, a brown oil, congeals after 10 hours
3. filtrationThe fine crystalline suspension is filtered by suction
4. washthe filter cake is washed with hexane