Sodium Carbonate → 2-(2-Methoxy-4-(1H-pyrazol-1-yl)phenyl)-5-((2,2,6,6-tetramethylpiperidin-4-yl)methyl)-1,3,4-thiadiazole

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 4] [39 mg, 0.128 mmol) and 2-bromo-5-((2,2,6,6-tetramethylpiperidin-4-yl)methyl)-1,3,4-thiadiazole (34 mg, 0.107 mmol) in dioxane (1 mL) was added Pd(PPh3)4 (6 mg, 0.005 mmol), followed by a solution of Na2CO3 (34 mg, 0.32 mmol) in water (0.25 mL). The reaction mixture was purged with nitrogen, sealed, and heated at 120° C. for 1 hour under microwave irradiation. The reaction mixture was diluted with DCM (20 mL) and washed with saturated NaHCO3(aq) (10 mL). The organic phase was separated and concentrated in vacuo to afford the crude product as a brown oily residue. The crude material was purified by UV directed preparative HPLC under acidic conditions (formic acid modified) and the product containing fractions were loaded onto a 1 g SCX cartridge (pre-wet with MeOH). The cartridge was washed with MeOH (10 mL) then flushed with 7M NH3 in MeOH (10 mL). The MeOH/NH3 was removed in vacuo to afford the title compound as a slightly off-white solid 28.6 mg, 65% yield). LC-MS: Rt 0.88 min; MS m/z 412.5 [M+H]+ [Method A]. 1H NMR (400 MHz, DMSO-d6) δ ppm 8.70 (d, J=2.53 Hz, 1H), 8.39 (d, J=8.59 Hz, 1H), 7.83 (d, J=1.01 Hz, 1H), 7.73 (d, J=1.52 Hz, 1H), 7.67 (dd, J=8.59, 2.02 Hz, 1H), 6.64-6.61 (m, 1H), 4.11 (s, 3H), 3.01 (d, J=6.57 Hz, 2H), 2.17-2.28 (m, 1H), 1.53 (dd, J=12.63, 2.53 Hz, 2H), 1.09 (s, 6H), 1.00 (s, 6H), 0.86 (t, J=12.38 Hz, 2H).

Provenance & Evidence