A solution of 1-(tert-butoxycarbonyl)-1,2,3,6-tetrahydropyridin-4-yl trifluoromethanesulfonate (Compound 1061, 2.65 g, 8 mmol, prepared according to the procedure described in Organic Letters, 3(15), pp. 2317-2320, 2001), 4-methylthiophene-2-boronic acid (1.14 g, 8 mmol), and sodium bicarbonate (1.01 g in 10 mL water, 12 mmol) in DMF (30 mL) was degassed with a nitrogen stream for 20 minutes. To the mixture was added tris(diphenylphosphinoferrocene) dichloropalladium (584 mg, 0.8 mmol) and the reaction was stirred for 10 minutes at 120° C. under microwave irradiation. The crude mixture was diluted with ethyl acetate and washed successively with water (2×15 mL) and brine (1×15 mL). The organic layer was dried over magnesium sulfate and concentrated under reduced pressure. The resulting residue was purified via silica gel chromatography to afford 1.67 g of tert-butyl 4-(4-methylthiophen-2-yl)piperidine-1-carboxylate (Compound 1062) as a yellow oil; ESMS (M+H)=224.
