Potassium Carbonate → methyl 5-methyl-4-(1-methyl-1H-pyrazol-5-yl)-2-thiophenecarboxylate

Participants

Reaction Conditions

Reaction Steps

To a 125 mL sealed flask was added methyl 4-bromo-5-methyl-2-thiophenecarboxylate (1.56 g, 6.64 mmol) [Prepared according to the procedure of Preparation 10], 1-methyl-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (1.67 g, 8.03 mmol) [prepared according to the procedure of Preparation 7], K2CO3 (2.76 g, 19.97 mmol) and Pd(PtBu3)2 (170 mg, 0.33 mmol) in 1,4-Dioxane (27 ml) and water (7 ml). The reaction mixture was heated to 85° C. in a sealed tube for 3 hours, cooled to room temperature and partitioned between H2O and CHCl3. The organic fraction was dried (Na2SO4), adsorbed onto silica and purified via column chromatography (0-15% EtOAc/Hexane). (385 mg, 1.4 mmol, 30%): LC-MS (ES) m/z=237 (M+H)+.

Provenance & Evidence