[CH3:1][C:2]([CH3:14])([CH3:13])[C:3]([NH:5][C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][C:7]=1[CH3:12])=[O:4].C([Li])CCC.[CH3:20][N:21]=[CH:22][C:23]1[CH:27]=[CH:26][S:25][CH:24]=1>O1CCCC1.CCCCCC.C1(C)C=CC=CC=1>[CH3:20][NH:21][CH:22]([C:23]1[CH:27]=[CH:26][S:25][CH:24]=1)[CH2:12][C:7]1[CH:8]=[CH:9][CH:10]=[CH:11][C:6]=1[NH:5][C:3](=[O:4])[C:2]([CH3:14])([CH3:13])[CH3:1]To a chilled, solution (-50° C.) of 19.13 g of 2,2-dimethyl-N-[(2-methyl)phenyl]propanamide in 200 ml of tetrahydrofuran was added, dropwise over 1.5 hours, 88 ml of a 2.5M solution of n-butyllithium in hexane. Upon completion of the addition, the resultant solution was stirred for 2 hours with cooling. A solution of 15.0 g of 3-thiophene-carboxaldehyde methylimine in 30 ml of toluene, was then added, dropwise over 15 minutes, to the cooled solution. Upon completion of the 3-thiophenecarboxaldehyde methylimine addition, the reaction mixture was stirred for 20 minutes at 0° C., quenched by the addition of 300 ml of water, concentrated, and extracted with dichloromethane. The combined extract was dried over anhydrous magnesium sulfate, filtered, and concentrated to an oil. HPLC of the oil (Water's Associates Prep LC/System 500; silica gel; methanol as the eluent) afforded a semipurified product which was subsequently chromatographed under otherwise identical conditions utilizing ethyl acetate, followed by methanol as eluents. Concentration of the appropriate fractions and trituration with hexane yielded 18.0 g of N-[2-[2-(methylamino)-2-(3-thienyl)ethyl]phenyl]-2,2-dimethylpropanamide. mp 81°-84° C.
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