反应详情

温度

50 °C

Following general procedure F using 2e (58 mg, 0.25 mmol), B2pin2 (127 mg, 0.50 mmol), [Ir(COD)OMe]2 (2.5 mg, 0.00375 mmol) and dtbpy (2.0 mg, 0.0075 mmol) in THF (1.25 mL). Stirred in vial at 50 °C for 20 hours. Analysis of crude 1 H NMR using internal standard 1,2‐dimethoxyethane showed 1.4:1 meta:para borylation in 77% yield (19% starting material remaining). The crude product was purified by silica gel chromatography (30% EtOAc in Petroleum Ether 40‐60 o C), however this gave a mixture of the borylated products and starting material, which were inseparable on silica (1.6:1:0.52 mixture of meta:para:starting material ratio, as determined by 1 H NMR), as a white solid (73 mg). The yield was corrected to account for the 20% of starting material. Corrected yield for the borylated products was 64 mg, 0.18 mmol, 71%. By subtracting the resonances for the meta isomer, the NMR data of the para isomer can be assigned as follows: