tert-Butyl [(1R,3R)-3-carbamoylcyclohexyl]carbamate → tert-butyl N-[(1R,3R)-3-[[4-(5,5-dimethyl-4,6-dihydropyrrolo[2,1-e]pyrazol-3-yl)-5-fluoro-2-pyridinyl]carbamoyl]cyclohexyl]carbamate

Participants

Reaction Conditions

Reaction Steps

Tetrakis(triphenylphosphine)palladium(0) (0.094 g, 0.08 mmol) was added to Racemic tert-butyl ((1R,3R)-3-carbamoylcyclohexyl)carbamate (0.235 g, 0.97 mmol),3-(2-chloro-5-fluoropyridin-4-yl)-5,5-dimethyl-5,6-dihydro-4H-pyrrolo[1,2-b]pyrazole (0.215 g, 0.81 mmol), (9,9-dimethyl-9H-xanthene-4,5-diyl)bis(diphenylphosphane) (0.094 g, 0.16 mmol) and cesium carbonate (0.791 g, 2.43 mmol) in 1,4-dioxane (6 mL) and water (1.200 mL). The resulting suspension was degassed for 10 minutes under nitrogen and then stirred at 100 °C for 48 hours. LCMS is complete, it needs this long. The mixture was cooled, diluted with water (40 ml), and extracted with EtOAc (3 x 20 ml). The combined organics were evaporated to crude material. The crude product was purified by flash silica chromatography, elution gradient 0 to 60% EtOAc in heptane. Pure fractions were evaporated to dryness to afford Racemic tert-butyl ((1R,3R)-3-((4-(5,5-dimethyl-5,6-dihydro-4H-pyrrolo[1,2-b]pyrazol-3-yl)-5-fluoropyridin-2-yl)carbamoyl)cyclohexyl)carbamate (0.322 g, 84 %) as a white foam.

Provenance & Evidence