A mixture of 2-(4-bromo-1H-pyrazol-1-yl)acetic acid (867 mg), tert-butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-5,6-dihydropyridine-1(2H)-carboxylate (1.2 g) and Pd(PPh3)4 (232 mg) in dioxane (15 mL) and sat. K2CO3 (7.5 mL) was heated at 100° C. overnight. After cooling down, EA was added and the mixture was washed with water and brine. The combined aq. layers were acidified to pH=2 with NaHSO4 and extracted with EA. The org. layers from the second extraction were dried (MgSO4), filtered off and evaporated in vacuo to afford 1.05 g of brown resin that was used without purification. LC-MS (B): tR=0.72 min; [M+H]+: 308.26.
