2-(furan-3-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane is a useful research chemical.
Furan-3-boronic acid pinacol ester is white to off-white solid powder at room temperature and pressure, it is insoluble in water but soluble in most organic solvents. It has high chemical reactivity, it has rich electron cloud density and is sensitive to strong oxidizing agents. Its chemical reaction activity mainly focuses on the borate unit in its structure, which can participate in oxidation, coupling and other reactions.
GENERAL METHOD: 3-bromofuran (1 mmol), pinacol ester of bisboronic acid (1.2 mmol) and dioxane (5 mL) were added to a 25 mL round bottom flask. KOAc (2 mmol) was then added and the mixture was stirred for 5 min at room temperature. PdII-TpTP catalyst (0.15 mol%) was added and the reaction mixture was placed in an oil bath preheated to 110 °C and refluxed with continuous stirring in the open system. The reaction progress was monitored by thin layer chromatography (TLC). Upon completion of the reaction, the mixture was cooled to room temperature, diluted with water (20 mL) and extracted with tert-butyl methyl ether (3 x 10 mL). The organic layers were combined and concentrated to give the crude product. The crude product was purified by silica gel column chromatography using a mixture of ethyl acetate and hexane (1:30) as eluent.
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[2] Journal of the American Chemical Society, 2017, vol. 139, # 2, p. 607 - 610
[3] Synlett, 2018, vol. 29, # 8, p. 1055 - 1060
