Br[C:2]1[CH:3]=[C:4]([CH:9]=[CH:10][C:11]=1[CH2:12][CH3:13])[C:5]([O:7][CH3:8])=[O:6].[Cu][C:15]#[N:16]>CN1C(=O)CCC1.O>[C:15]([C:2]1[CH:3]=[C:4]([CH:9]=[CH:10][C:11]=1[CH2:12][CH3:13])[C:5]([O:7][CH3:8])=[O:6])#[N:16]Methyl 3-bromo-4-ethyl-benzoate (D44) (5 g) in NMP (180 mL) was treated with copper (I) cyanide (3.69 g). The mixture was then heated at reflux for 5 h, under argon. After cooling to 20° C. the reaction mixture was diluted with water, then filtered through kieselguhr, washing well with water and EtOAc. The organic layer was washed with water, brine and dried over MgSO4. The solvent was evaporated to dryness in vacuo and the residue was purified by chromatography on silica eluting with EtOAc-Hexane (1:9) to give the title compound (1.9 g) 1H NMR (CDCl3) δ 1.33 (3H, t), 2.94 (2H, q), 3.94 (3H, s), 7.43 (1H, d), 8.17 (1H, dd), 8.28 (1H, d).
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