4-Methylpyridine → (R)-4-(4-bromophenyl)-1-(pyridin-4-yl)-4-o-tolylbutan-2-one

Beteiligte Stoffe

Reaktionsschritte

At −78° C., to a solution of 4-methylpyridine (308 mg) in THF (7 mL) n-butyllithium (1.6M in hexane, 2.07 ml) was added. The reaction mixture was warmed slowly to rt, stirred for 1 h at that temperature, and cooled down again to −78° C. (R)-3-(4-Bromophenyl)-N-methoxy-N-methyl-3-o-tolylpropanamide (example 142, step 1; 400 mg) in THF (3 mL) was added slowly and the reaction mixture was warmed to rt and stirred for 3 h. The mixture was poured into a saturated aqueous solution of NaHCO3 (10 mL), the phases were separated, and the inorganic one was extracted with EtOAc (2×10 mL). The organic layers were combined, washed with brine, dried over Na2SO4 and concentrated in vacuo. The crude material was purified by flash chromatography on silica gel (30% to 60% EtOAc in n-heptane to CH2Cl2/MeOH 9:1) to yield the title compound as a yellow oil (220 mg, 51%), MS (ESI+): m/z=394.0 ([M+H]+, 1Br).

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