alpha-Phenylcinnamic acid, (Z)- → 1504-52-5

Participants

Reaction Conditions

Reaction Steps

Sodium bis-(2 -methoxye thoxy ) aluminum hydride (70% in toluene) (Vitride®, 536 g, 1.86 mol) was diluted with 850 mL of toluene and the solution was cooled to -10° C. under a nitrogen atmosphere. A 170 g (0.74 mol) sample of Z-2,3-diphenyl propenoic acid was added portionwise to the Vitride solution while maintaing the temperature of the reaction below 10° C. The resulting mixture was stirred at 0°-5° C. until thin layer chromatography indicated total consumption of the carboxylic acid (1.5 hours). A 1.7 L sample of n-butanol was added slowly at about 25° C. until the exotherm and foaming subsided. The speed of addition of the butanol was increased as the exotherm and foaming stabilized. The pH of the resulting cloudy mixture was adjusted from 11 to 3.5-4.0 with 1.66 L of 3 N aqueous HCl. The layers were separated. The organic layer was washed two times with water and dried (Na2SO4). The mixture was filtered and the drying agent was washed with 1:1 n-butanol:toluene (500 mL). The filtrate was evaporated in vacuo to give 170 g of an amber oil which crystallized on the addition of 50 mL of toluene and 510 mL of heptane. The solid precipitate was collected, washed with heptane, and dried to a constant weight under vacuum at 40° C.

Provenance & Evidence