Benzyl Alcohol → (+/-)-2-[[Phenylmethoxy(4-phenylbutyl)phosphinyl]oxy]propionic acid, ethyl ester

Participants

Reaction Steps

A mixture of 4-phenylbutyl phosphonic acid from Part A (0.70 g, 3.27 mmole), benzene (10 ml), and PCl5 (1.36 g, 6.54 mmole) was refluxed under argon for 30 minutes. The benzene and POCl3 were removed in vacuo and the residue taken up in CH2Cl2 (5 ml). After cooling to 0° C. (ice-bath), triethylamine (1.3 ml, 9.39 mmole) was added followed by dropwise treatment with d,1 ethyl lactate (0.39 ml, 3.3 mmole) in CH2Cl2 (3 ml) over a 5 minute period. After 1 hour benzyl alcohol (0.35 ml, 3.3 mmole) in CH2Cl2 (3 ml) was added dropwise over 2 minutes, the ice-bath removed, and the reaction mixture allowed to stir for 2 hours. The reaction mixture was diluted with EtOAc then washed with H2O, 5% KHSO4, saturated NaHCO3, brine, dried (MgSO 4), and evaporated. The residue (1.3 g) was chromatographed on silica (70 g) eluting with 2/1 hexane/EtOAc to obtain the title compound (0.80 g, 1.98 mmole; 60% yield) as an oil.

Provenance & Evidence