Example XIV: Synthesis of 2-cyclopent-1-enyl-4,4,5,5-tetramethyl-[1,3,2]dioxaborolane
Under argon protection, 4.31 g of 1-chloro-1-cyclopentene and 12.5 g of bis(pinacolato)diboron were dissolved in 160 mL of 1,4-dioxane, 8 g of potassium acetate was added, and argon purged for 5 min. Subsequently, 370 mg of tris(dibenzylideneacetylidene)dipalladium(0) ([Pd2(dba)3]) and 780 mg of 2-cyclohexylphosphino-2',4',6'-triisopropyl-1,1'-biphenyl were added, and the reaction mixture was heated to 80 °C for 3 hours. After completion of the reaction, it was cooled to room temperature, diluted with diethyl ether, the organic phase was washed with water and brine sequentially, and the organic phase was dried with anhydrous magnesium sulfate. The solvent was removed by evaporation under reduced pressure and the residue was ground with petroleum ether. The precipitate was collected by filtration and the mother liquor was evaporated under reduced pressure to obtain the product. Yield: 13.1 g (99% yield). Mass spectrum (EI): m/z = 194 [M]+.
