[H-].[Na+].[C:3]([O:11][CH2:12][CH3:13])(=[O:10])[CH2:4][C:5]([O:7][CH2:8][CH3:9])=[O:6].Br[C:15]1[CH:20]=[CH:19][N:18]=[C:17]2[CH:21]=[CH:22][S:23][C:16]=12>O1CCOCC1.[Cu]Br>[CH2:12]([O:11][C:3](=[O:10])[CH:4]([C:15]1[CH:20]=[CH:19][N:18]=[C:17]2[CH:21]=[CH:22][S:23][C:16]=12)[C:5]([O:7][CH2:8][CH3:9])=[O:6])[CH3:13]Charge a flask containing sodium hydride (17.45 g, 0.44 moles) with anhydrous dioxane (500 ml) while cooling at 0° C. Add diethyl malonate (69.88 g, 0.44 moles) dropwise over one hour. Upon reaching ambient temperature, add copper (I) bromide (62.59 g, 0.44 moles). Add 7-bromothieno[3,2-b]pyridine (18.68 g, 87.26 mmol) as a solution in dioxane (50 mL). Heat the reaction to reflux for 18 hours. Concentrate the reaction solution to ˜175 mL. Pour the concentrate into concentrated ammonium hydroxide (2.5 L). Extract the aqueous phase with ethyl acetate (6×300 mL). Wash the organic layers exhaustively with 2 N sodium hydroxide until the blue color dissipates. Treat the organic layers with magnesium sulfate, filter and concentrate. Purification on silica utilizing a solution of 1:1:3 of ether, ethyl acetate and hexane as eluent yields the desired compound (14.6 gm, 57%).
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