4-BUTOXY-3-CHLOROPHENYLBORONIC ACID synthesis

Yield:1401165-55-6 82%

Reaction Conditions:

with caesium carbonate;dichloro(1,1'-bis(diphenylphosphanyl)ferrocene)palladium(II)*CH₂Cl₂ in 1,4-dioxane at 20 - 80;

Steps:

262A 6-(4-butoxy-3-chlorophenyl)picolinaldehyde

Example 262A 6-(4-butoxy-3-chlorophenyl)picolinaldehyde To a solution of 6-bromopicolinaldehyde (4.07 g, 21.88 mmol) in dioxane (40 mL) at ambient temperature was added 4-butoxy-3-chlorophenylboronic acid (5.00 g, 21.9 mmol), 2M cesium carbonate (22.0 mL, 43.8 mmol) and 1,1'-bis(diphenylphosphino)ferrocene-palladium(II)dichloride dichloromethane complex (0.357 g, 0.438 mmol). The mixture was degassed (3* vacuum/purge N₂) then heated at 80° C. overnight. The mixture was cooled to room temperature then partioned between water and CH₂Cl₂. The organic phase was concentrated and purified by chromatography (silica gel, 10% ethyl acetate:hexanes) to provide 5.20 g (82%) of the title compound. MS (DCI+) m/z 290 (M+H).

References:

US2012/245124,2012,A1 Location in patent:Page/Page column 70