[CH3:1][O:2][C:3]1[C:8]([O:9][CH3:10])=[CH:7][CH:6]=[CH:5][C:4]=1[CH3:11].CN(C)CCN(C)C.C([Li])CCC.CCCCCC.CN([CH:34]=[O:35])C.[Cl-].[NH4+]>CCOCC>[CH3:10][O:9][C:8]1[C:3]([O:2][CH3:1])=[C:4]([CH3:11])[CH:5]=[CH:6][C:7]=1[CH:34]=[O:35]2,3-Dimethoxytoluene (2 g, 13.1 mmol) was weighed in a flask and ether was added to the flask. N,N,N′,N′-tetramethylethylenediamine (422 mg, 3.6 mmol) was added to the solution. While stirring, the mixture was cooled down to 0° C. and n-Butyl lithium 1.6M in hexane (2.25 mL, 3.6 mmol) was added slowly over 20 minutes. The solution was stirred at 0° C. for 30 minutes after which the ice bath was removed. The solution became yellow during addition and after removal of the ice bath, a precipitate started forming. The reaction mixture was left stirring overnight at room temperature under nitrogen then cooled down again to 0° C. and DMF (1.23 mL, 15.9 mmol) was added. The homogeneous reaction mixture was stirred at this temperature for 1 hour. The solution was poured onto crushed ice and 15 mL ammonium chloride 1N. The phases were separated and the organic phase was washed with 4 portions of 1N ammonium chloride. The organics were dried over sodium sulphate, filtered and the filtrate was evaporated under vacuum. The crude product was purified on normal silica with DCM to yield 1.27 g (58%) of 14 which was used in the next stage.
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