[Cl-].[Li+].C(OP([CH2:11][C:12]([O:14][CH2:15][CH3:16])=[O:13])(OCC)=O)C.C1CCN2C(=NCCC2)CC1.[F:28][C:29]([F:35])([F:34])[CH2:30][CH2:31][CH:32]=O>CC#N>[F:28][C:29]([F:35])([F:34])[CH2:30][CH2:31]/[CH:32]=[CH:11]/[C:12]([O:14][CH2:15][CH3:16])=[O:13]To a suspension of lithium chloride (0.504 g, 11.9 mmol) in MeCN (20 mL) were added ethyl 2-(diethoxyphosphoryl)acetate (available from Aldrich) (1.91 mL, 9.52 mmol) and DBU (1.42 mL, 9.52 mmol) at room temperature. The mixture was cooled to 0° C., and 4,4,4-trifluorobutanal (available from Matrix Scientific) (1.00 g, 7.93 mmol) was added dropwise. The resulting mixture was warmed to room temperature and stirred overnight. The mixture was partitioned between water and EtOAc. The layers were separated, and the aqueous phase was extracted with additional EtOAc. The combined organic layers were washed with water and brine, dried (MgSO4), and concentrated. The residue was purified by silica gel flash chromatography (0-10% EtOAc/hexane) to afford (E)-ethyl 6,6,6-trifluorohex-2-enoate 68.B (6:1 E/Z) as a colorless liquid (1.13 g, 73%).
Loading…