[C:1](=[C:4]([C:7]#[N:8])[C:5]#[N:6])([CH3:3])[CH3:2].Br[CH2:10][C:11]([O:13][CH2:14][CH3:15])=[O:12]>[Zn].C1COCC1>[C:5]([CH:4]([C:7]#[N:8])[C:1]([CH3:3])([CH3:2])[CH2:10][C:11]([O:13][CH2:14][CH3:15])=[O:12])#[N:6]Zinc powder (1.23 g, 18.85 mmol) was added to a THF (20 mL) solution of isopropylidenemalononitrile (1.0 g, 9.42 mmol), ethyl bromoacetate (3.15 g, 18.85 mmol) and titanium bis(cyclopentadienyl)dichloride (235 mg, 0.94 mmol). After stirring for 1 hour the solution was partitioned between ethyl acetate and aqueous 1N HCl. The organic phase was washed with water, brine, dried over MgSO4 and filtered. The solution was concentrated and the crude residue purified by silica gel chromatography using a hexanes/EtOAc gradient to give the indicated product. 1H NMR (400 MHz, CD3CN): δ 4.55 (s, 1H); 4.10 (q, J=7.2 Hz, 2H); 2.48 (s, 2H); 1.24 (s, 6H); 1.21 (t, J=7.2 Hz, 3H).
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