1,4-Dioxane → tert-butyl 4-(5-bromo-1,3,4-thiadiazol-2-yl)-5,6-dihydropyridine-1(2H)-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a 5 mL microwave vial was added tert-butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-5,6-dihydropyridine-1(2H)-carboxylate (247 mg, 0.8 mmol), 2,5-dibromo-1,3,4-thiadiazole (98 mg, 0.4 mmol), K3PO4 (212 mg, 1.0 mmol), Pd(PPh3)4 (23 mg, 0.02 mmol), 1,4-dioxane (2 mL), and water (0.4 mL). The mixture was purged with N2 for 10 min, then heated to 100° C. in the microwave for 1 hour. The mixture was diluted with EtOAc, washed with water and brine, dried over Na2SO4, and concentrated in vacuo. The residue was purified by column chromatography (EtOAc/Heptane) to afford 64 mg (46%) of tert-butyl 4-(5-bromo-1,3,4-thiadiazol-2-yl)-5,6-dihydropyridine-1(2H)-carboxylate: MS (M+2)=348.1; 1H NMR (400 MHz, CHLOROFORM-d) δ 6.46 (td, J=3.0, 1.9 Hz, 1H), 4.15 (d, J=3.0 Hz, 2H), 3.64 (t, J=5.6 Hz, 2H), 2.73 (m, 2H), 1.49 (s, 9H).

Provenance & Evidence