Triethylamine → 2-Amino-4-chlorophenylboronic acid pinacol ester

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-bromo-5-chloroaniline (20.0 g, 96.9 mmol) in 1,4-dioxane (200 ml) were added triethylamine (54.0 ml, 487 mmol) and [1,1-bis(diphenylphosphino)ferrocene]dichloropalladium(II) dichloromethane complex (3.96 g, 4.84 mmol), and under a nitrogen stream, 4,4,5,5-tetramethyl-1,3,2-dioxaborolane (42.3 ml, 290 mmol) was added dropwise. The mixture was stirred at 100° C. for 10.5 hr. The mixture was allowed to cool to room temperature and filtered through celite. To the filtrate was added dropwise methanol (25 ml) at 0° C. The solvent was evaporated under reduced pressure, and the obtained residue was purified by silica gel chromatography (hexane:ethyl acetate=20:1) to give 5-chloro-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenylamine (16.5 g, yield. 65%).

Provenance & Evidence