2-PROPEN 2- BROMO-3-PHENYL-, ACETATE

ACETATE], 32 1 Propene, 2-methyl-, 35 2-Propen-l-ol, 2-bromo 3-phenyl-, acetate, 35... 

To a 2 L, 3-neck Morton flask fitted with a thermometer, a mechanical stirrer, and an addition funnel was added the methyl 3-hydroxy-2-methylene-3-phenylpropionate (305.9 g, 1.585 mol) followed by addition of 48% HBr (505 ml, 4.46 mol) in one portion. The flask was immersed in an ice-water bath, at which time concentrated sulfuric acid (460 ml, 8.62 mol) was added dropwise over 90 min and the internal temperature of the reaction mixture was maintained at 23°-27°C throughout the addition process. After removal of the ice-water bath, the mixture was allowed to stir at room temperature overnight. The solution was then transferred to a separatory funnel and the organic layer was allowed to separate from the acid layer. The acids were drained and the organic layer was diluted with 2 L of a 1 1 ethyl acetate/hexane solution, washed with saturated aqueous sodium bicarbonate solution (1 L), dried over sodium sulfate, and concentrated to yield 400.0 g (99%) of the desired (Z)-l-bromo-2-carbomethoxy-3-phenyl-2-propene as a light yellow oil, which was used without any additional purification, boiling point 180°C (12 mm). 

The cis and trans diaiylpropenamine isomers were isolated from feces, derivativized with 3-(4 -bromo-[ 1,1 -biphenyl]-4-yl)-3-(phenyl-i W-dimethyl-2-propen-1 -amine), and analyzed on a silica column (2 — 272 nm). Baseline resolution and excellent peak shapes were achieved along with complete elution in <10min with a 59/20/1 ethyl acetate/hexane/triethylamine mobile phase [859]. A linear range of 10-150pg/mL and with a detection limit of 2pg/mL were reported. 

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