Sodium Carbonate → tert-butyl 5,6-dihydro-4-(4-nitrophenyl)pyridine-1(2H)-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-nitrophenylboronic acid pinacol ester (4.5 g; 18.1 mmol; 1.2 eq.), tert-butyl 4-{[(trifluoromethyl)sulfonyl]oxy}-3,6-dihydropyridine-1(2H)-carboxylate (5.0 g; 15.1 mmol; 1.0 eq.) and sodium carbonate (1.07 g, 10.1 mmol, 5 eq.) were dissolved in DME (50 mL) and water (25 mL). The mixture was degassed for 5 min with nitrogen before the addition of Pd(PPh3)4 (349 mg; 0.30 mmol; 0.02 eq.) and heated at 80° C. O/N. Water (100 mL) was added and aqueous phase was extracted with EtOAc (twice). Combined organic phases were washed with brine, dried over magnesium sulfate, filtered and concentrated. The crude was purified by flash chromatography on silica (EtOAc:heptane, 10.90) to give the title compound as a yellow solid (3.3 g, 72%). 1H NMR (300 MHz, DMSO-d6) δ 8.24-8.17 (m, 2H), 7.65-7.68 (m, 2H), 6.45 (brs, 1H), 4.06 (m, 2H), 3.56 (t, 2H), 2.55-2.48 (m, 2H), 1.43 (s, 9H).

Provenance & Evidence