Allyl bromide → (R)-N-(2-(allyloxy)-1-phenylethyl)-2,2,2-trifluoroacetamide

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Reaction Steps

Step Q (2): (R)-2,2,2-Trifluoro-N-(2-hydroxy-1-phenylethyl)acetamide from step Q (1) (3.34 g, 14.3 mmol) was dissolved in THF (30 mL) and chilled to −78° C. n-BuLi (12 mL, 29 mmol, 2.5 M in hexanes) and DMPU (3.45 mL, 29 mmol) were added to the mixture. After 10 min, allyl bromide (12 mL, 143 mmol) was added. The mixture was warmed to rt and then heated to reflux for 16 h. The mixture was quenched with saturated NH4Cl, diluted with 1 N NaOH, and extracted with EtOAc. The combined organic layers were dried over Na2SO4, filtered, and concentrated in vacuo. Purification by silica-gel column chromatography (0-25% EtOAc/Hexanes) afforded 2.88 g (73% yield) of (R)-N-(2-(allyloxy)-1-phenylethyl)-2,2,2-trifluoroacetamide as a yellow residue. LC-MS (M+H)+=274.06. 1H NMR (300 MHz, CDCl3) δ ppm 3.66-3.79 (m, 2H) 3.95-4.01 (m, 2H) 5.07-5.26 (m, 3H) 5.73-5.89 (m, 1H) 6.95-7.06 (m, 1H) 7.24-7.37 (m, 4H).

Provenance & Evidence