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 1a (3.8 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 10.2:1 meta:para borylation in 80% 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 (10.5:1:2.0 mixture of meta:para:starting material ratio, as determined by 1 H NMR), as a white solid (76 mg). As the mixture contained 15% of starting material, the isolated yield was corrected by calculating the mass of the starting material in the mixture. Corrected yield for the borylated products was 68 mg, 0.19 mmol, 76%.