[CH3:1][N:2]1[CH:6]=[CH:5][N:4]=[N:3]1.[Li]CCCC.[Cl:12][C:13]1[CH:20]=[CH:19][C:16]([CH:17]=[O:18])=[CH:15][CH:14]=1>C1COCC1>[Cl:12][C:13]1[CH:20]=[CH:19][C:16]([CH:17]([C:6]2[N:2]([CH3:1])[N:3]=[N:4][CH:5]=2)[OH:18])=[CH:15][CH:14]=1Analogous to the general method described in J. Org. Chem. 2004, 69, 8115, and Chem. Pharm. Bull, 1997, 1145. To a 2-necked flask containing 1-methyl-1H-1,2,3-triazole (1.00 g, 12.0 mmol, Intermediate 42, step a) was added THF (75 mL) and the solution was cooled between −40 to −20° C. To this colorless homogeneous solution was added n-BuLi (2.5 M in hexanes, 5.0 mL, 11.4 mmol) dropwise which afforded a dark brown viscous mixture. After stirring at 0° C. for 1 hours, a THF (10 mL) solution of 4-chlorobenzaldehyde (1.60 g, 11.4 mmol) was introduced and the reaction mixture began to be stirred freely and remained brownish. After 3 hours the reaction mixture was quenched by pouring into a saturated solution of NH4Cl and the aqueous portion was extracted with EtOAc (4×50 mL). The combined organics were washed with brine, dried over MgSO4, filtered and concentrated to give a brown oil which solidified upon standing. The crude material was triturated with Et2O to provide the title compound as a brown solid.
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