[S:1]1[CH:5]=[CH:4][N:3]=[CH:2]1.[Li]CCCC.CCCCCC.[CH3:17][C:18]([CH3:28])([CH3:27])/[CH:19]=[N:20]/[S:21]([C:23]([CH3:26])([CH3:25])[CH3:24])=[O:22]>C1COCC1>[CH3:17][C:18]([CH3:28])([CH3:27])[CH:19]([NH:20][S:21]([C:23]([CH3:26])([CH3:25])[CH3:24])=[O:22])[C:2]1[S:1][CH:5]=[CH:4][N:3]=1To a solution of thiazole (247 mg, 206 μl, 2.91 mmol) in 10 mL dry THF under argon at −73° C. was slowly added a 1.6M solution of BuLi in hexane (1.82 ml, 2.91 mmol). The resulting reaction mixture was stirred at −75° C. for 30 min and a solution of (E)-N-(2,2-dimethylpropylidene)-2-methylpropane-2-sulfinamide (Example 306a) (500 mg, 2.64 mmol) in 5 mL dry THF was added. The reaction mixture was stirred at −75° C. for 30 min, then cooling bath was removed and reaction stirred at r.t for 1 h. The reaction was quenched by the addition of few drops of water, the reaction mixture poured into ethyl acetate, and the solution was then extracted with aqueous NaHCO3 1M. The organic phase was collected, dried over Na2SO4 and evaporated down to dryness to give the title compound (666 mg, 92%) as crude dark orange oil. The crude was used without any further purification, MS (EI): m/e=275.2 [M+H]+.
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