Br[CH2:2][C:3]([O:5][CH2:6][CH3:7])=[O:4].[N:8]1[CH:13]=[CH:12][CH:11]=[CH:10][C:9]=1[CH:14]([C:17]1[C:22]([CH3:23])=[CH:21][C:20]([CH3:24])=[CH:19][C:18]=1[CH3:25])[C:15]#[N:16].C(=O)([O-])[O-].[K+].[K+].CC(C)([O-])C.[K+]>CS(C)=O.[NH4+].[Cl-]>[NH2:16][C:15]1[C:14]([C:17]2[C:22]([CH3:23])=[CH:21][C:20]([CH3:24])=[CH:19][C:18]=2[CH3:25])=[C:9]2[N:8]([C:2]=1[C:3]([O:5][CH2:6][CH3:7])=[O:4])[CH:13]=[CH:12][CH:11]=[CH:10]2
Slowly add dropwise ethyl bromoacetate (23 mL; 0.21 mol) over a 3-hour period to a mixture of 2-(2-pyridinyl)-2-(2,4,6-trimethylphenyl)-ethanenitrile (22.3 g; 0.094 mol) and potassium carbonate (78 g; 0.57 mol) suspended in DMSO (100 mL). Stir the mixture for 1 day, pour into an aqueous NH4Cl solution (ca. 1 L), and extract with 3×200 mL of Et2O. Wash the combined extracts with saturated brine, dry over Na2SO4, filter, and concentrate in vacuo. Dissolve the residue in THF (200 mL), cool to 0° C., and add slowly in portions potassium t-butoxide (12 g; 0.11 mol) over a 10-minute period. After 30 minutes at 0° C., dilute the mixture with aqueous NH4Cl and extract with 2×150 mL of 50% Et2O in hexane. Wash the combined extracts with saturated brine, dry over Na2SO4, filter, concentrate in vacuo, and purify by column chromatography on silica gel (eluent: 5 to 10% EtOAc in hexane) to obtain the title compound as an oil: 1H NMR (400 MHz, CDCl3) δ 1.47 (t, 3H), 2.06 (s, 6H), 2.35 (s, 3H), 4.46 (br q, 2H), 6.6 (br t, 1H), 6.75 (d, 1H), 6.9 (br t, 1H), 7.00 (s, 2H), 9.4 (1H).
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