Potassium Acetate → {6-Chloro-5-[(methylsulfonyl)amino]-3-pyridinyl}boronic acid

Participants

Reaction Conditions

Reaction Steps

N-(5-Bromo-2-chloro-3-pyridinyl)methanesulfonamide (5 g, 17.51 mmol), potassium acetate (5.16 g, 52.5 mmol), 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi-1,3,2-dioxaborolane (4.89 g, 19.26 mmol) and 1,1′-bis(diphenylphosphino)ferrocene palladium dichloride (1.281 g, 1.751 mmol) were placed in 1,4-dioxane (51 ml) and the mixture heated for 16 h at 90° C. The reaction was left stirring at 90° C. for a further 5 h. Further catalyst (0.3 g), potassium acetate (1.7 g) and 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi-1,3,2-dioxaborolane (1.5 g) were added and the mixture stirred at 95° C. overnight. The mixture was cooled to room temperature then the mixture was filtered through a hydrophobic frit and the solvent removed in vacuo. The residue was partitioned between water (250 ml) and dichloromethane (250 ml). the organic layer was collected and the solvent removed in vacuo. The residue was columned on silica (3×100 g) cartridges eluting with 0-25% methanol in dichloromethane over 40 mins gave the title compound as a dark brown oil (4.9 g).

Provenance & Evidence