反应详情

A mixture of divinylphenylphosphine oxide (0.40g, 2.24 mmol) and aqueous methylamine (2.6 ml of 1M = 2.7 mmol) was heated under reflux for 30 min. The aqueous solution was cooled, saturated with ammonium chloride, and extracted with chloroform. Bulb to bulb distillation of the product at 140°/0.005 mm gave 1-methyl-4-oxo-4-phenylperhydro-1,4-azaphosphorine (0.46g, 98%), as colourless hydroscopic crystals, m.p. 115°-116°. The m.p. was not raised by recrystallization from anhydrous benzene, cyclohexane (1:3). The purity of this material was confirmed by t.l.c. (chloroform-methanol (3:1)). A freshly dried sample (80°/5 mm over P2O5) gave slightly low carbon and phosphorus values owing to rapid uptake of water prior to analysis (Found: C, 62.6; H, 7.8; P, 14.6. C11H16NOP requires C, 63.2; H, 7.7; P, 14.8%). Mol. wt. (Mass spectrum), 209. Infrared spectrum νmax (Nujol): 2820 (N--CH2), 1590, 1460 (C6H5 --P), 1410, 1380, 1320, 1265, 1170, (P=O), 1110, 1065, 990, 960, 925, 810, 760, 725, 705, 665 cm-1. N.m.r. spectrum (CDCl3): 7.82, dm, 2H (o-aromatic); 7.4-7.7, m, 3H (m- and p-aromatic); 2.6-3.3, m, 4H (methylenes); 2.36, s, 3H (methyl); 1.8-2.5, m, 4H (methylenes). A sample which had been exposed to the atmosphere for a few min showed additional broad absorption bands at 3400 and 1630 cm-1 in the i.r. spectrum, and additional sharp singlets at δ3.06 and 4.62 (exchanged by D2O) in the n.m.r. spectrum.

1. temperaturewas heated
2. temperatureunder reflux for 30 min
3. extractionextracted with chloroform
4. distillationBulb to bulb distillation of the product at 140°/0.005 mm