Sodium Carbonate → tert-Butyl 4-(5-(2-methoxy-4-(1H-pyrazol-1-yl)phenyl)-1,3,4-thiadiazol-2-yl)piperazine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a stirred suspension of 1-(3-methoxy-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-1H-pyrazole [Intermediate 1] (132 mg, 0.441 mmol) and tert-butyl 4-(5-bromo-1,3,4-thiadiazol-2-yl)piperazine-1-carboxylate (140 mg, 0.401 mmol) in dioxane (2 mL) was added Pd(PPh3)4 (23 mg, 20 μmol) followed by a solution of Na2CO3 (85 mg, 0.802 mmol) in water (0.5 mL). The reaction mixture was purged with nitrogen, sealed, and heated at 120° C. for 30 minutes under microwave irradiation. The reaction mixture was cooled to room temperature, diluted with DCM (20 mL), washed with water (10 mL), then the organic phase was separated and concentrated in vacuo to afford the crude product as a pale brown solid. The crude material was purified by flash chromatography using a 12 g silica cartridge running an EtOAc/heptane gradient to afford the title compound as a pale yellow/off-white solid (138 mg, 78% yield). LC-MS: Rt 1.34 min; MS m/z 443.3 [M+H]+ [Method A]. 1H NMR (400 MHz, DMSO-d6) δ ppm 8.65 (d, J=2.53 Hz, 1H), 8.21 (d, J=8.59 Hz, 1H), 7.80 (d, J=1.52 Hz, 1H), 7.66 (d, J=2.02 Hz, 1H), 7.60 (dd, J=8.59, 2.02 Hz, 1H), 6.59-6.62 (m, 1H), 4.05 (s, 3H), 3.51 (s, 8H), 1.43 (s, 9H).

Provenance & Evidence