[C:1]([C:3]1[CH:12]=[CH:11][C:6]([C:7]([O:9][CH3:10])=[O:8])=[CH:5][CH:4]=1)#[N:2].[CH2:13]([Mg]Br)[CH3:14].B(F)(F)F.CCOCC.Cl>C(OCC)C.[Ti+4]>[NH2:2][C:1]1([C:3]2[CH:12]=[CH:11][C:6]([C:7]([O:9][CH3:10])=[O:8])=[CH:5][CH:4]=2)[CH2:14][CH2:13]1
To the solution of methyl 4-cyanobenzoate (100 g, 620 mmol) in diethyl ether (3 L) was added titanium (IV) isospropoxide (194 g, 682 mmol), followed by dropwise addition of ethylmagnesium bromide 3M solution in diethylether (450 ml, 1.36 mol) at −70° C. The mixture was stirred for 1 h, and then boron trifluoride etherate (157 ml, 1.24 mol) was added at once. After 2 hours, aqueous HCl (5%) was added until the pH showed acidy, then the mixture was filtered. The solid was washed with ethylacetate. The aqueous phase was separated and the organic layer was washed with water. All aqueous layers were collected together, basified with 1M NaOH and extracted with ethylacetate. The organic layer was dried (Na2SO4) and concentrated to afford the title compound (D6) (32.0 g).
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