Cesium carbonate → methyl 6-[bis-(tert-butoxycarbonyl)amino]-3-[2-(tetrahydropyran-2-yl)-2H-pyrazol-3-yl]-2-vinylbenzoate

Participants

Reaction Conditions

Reaction Steps

A mixture of methyl 6-[bis-(tert-butoxycarbonyl)amino]-3-[2-(tetrahydropyran-2-yl)-2H-pyrazol-3-yl]-2-trifluoromethanesulfonyloxybenzoate (Intermediate 11, 4.35 g), vinylboronic acid pinacol ester (1.9 mL), bis(triphenylphosphine)palladium (II) dichloride (0.255 g) and cesium carbonate (7.1 g) in dioxane (300 mL) and water (47 mL) was de-gassed and purged with nitrogen. The mixture was then heated to 80° C. for 4 hours. After cooling, the mixture was diluted with ether and the organic layer was separated, dried (MgSO4) and filtered. The filtrate was concentrated in vacuo and the residue was purified by chromatography on silica, eluting with a mixture of ethyl acetate and cyclohexane with a gradient of 0-60% to give methyl 6-[bis-(tert-butoxycarbonyl)amino]-3-[2-(tetrahydropyran-2-yl)-2H-pyrazol-3-yl]-2-vinylbenzoate (2.84 g) as a gum.

Provenance & Evidence