[Li]CCCC.[CH3:6][C:7]#[N:8].CO[C:11](=[O:25])[C:12]1[CH:17]=[CH:16][CH:15]=[C:14]([O:18][CH3:19])[C:13]=1[N:20]=[CH:21]N(C)C>C1COCC1>[CH3:19][O:18][C:14]1[CH:15]=[CH:16][CH:17]=[C:12]2[C:13]=1[NH:20][CH:21]=[C:6]([C:7]#[N:8])[C:11]2=[O:25]To 35.0 mL of THF was added 26.6 mL (66.4 mmol ) of n-BuLi solution during 5 min at −78° C. To the stirred solution was added a solution of 3.55 mL (67.9 mmol) of CH3CN in 65 mL of THF during 10 min which time the solution became white suspension, and then continued to stir for 15 min at −78° C. To the suspension was added a solution of 5.8 g (24.5 mmol) of 2-(Dimethylamino-methyleneamino)-3-methoxy-benzoic acid methyl ester in 45 mL of THF during 30 min, and then continued to stir 30 min at −78° C. during which time the mixture gradually became clear. The solution was quenched with 8.5 mL of HOAc. The resulting thick slurry was stirred and warmed to room temperature. After most of the solvent was evaporated, the residue was diluted with cold water. The separate solid was collected by filtration and washed with water. After drying in vacuo, this afforded 3.8 g of the product as an off white solid in 77.6% of yield, m.p. 270° C. (dec.), mass spectrum (electrospray, m/e): M+H 201.1
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