[CH2:1]([Mg]Br)[CH3:2].[CH2:5]([O:12][C:13]1[C:20]([F:21])=[CH:19][CH:18]=[CH:17][C:14]=1[C:15]#[N:16])[C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1.B(F)(F)F.CCOCC>C(OCC)C.CC([O-])C.CC([O-])C.CC([O-])C.CC([O-])C.[Ti+4]>[CH2:5]([O:12][C:13]1[C:20]([F:21])=[CH:19][CH:18]=[CH:17][C:14]=1[C:15]1([NH2:16])[CH2:2][CH2:1]1)[C:6]1[CH:7]=[CH:8][CH:9]=[CH:10][CH:11]=1A solution of ethylmagnesium bromide, 3M in diethyl ether (28.2 mL) was added as a slow stream to a mechanically stirred mixture of tetraisopropyl orthotitanate (13.09 mL,) and 2-(benzyloxy)-3-fluorobenzonitrile (Example 283a, 9.6 g) in diethyl ether (400 mL) cooled to −78° C. The resulting solution was stirred at −78° C. for 15 min and then warmed to room temperature over 1 h 30 min. An ice bath was placed around the reaction and boron trifluoride etherate (10.71 mL) was added as a slow stream (caution exothermic) and the mixture was stirred for 30 min. The reaction was cooled (ice bath) and quenched with 1 M aqueous HCl (400 mL added portionwise). The aqueous layer was separated and the diethyl ether layer further extracted into 1M HCl (2×200 mL) (ethyl acetate added to the diethyl ether to aid solubility). The aqueous layer was cooled in an ice bath and basified with stirring with a 10M aqueous NaOH solution. The resulting precipitate was filtered through Celite, washing the pad with water (200 mL) then DCM (4×200 mL) then DCM/MeOH (90:10, 300 mL). The combined filtrates were separated and the aqueous layer further extracted with DCM (2×200 mL). The combined organics were dried (MgSO4) and evaporated, the residue was purified on SCX resin (50 g) eluting with DCM, methanol (discarded) and flushing with 20% ammonia in methanol to give the subtitle compound as an oil (2.54 g).
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