Phenylboronic acid, homocoupling

The Suzuki reaction has also been reported in [C4C4im][BF4] using ultrasound as the energy source.48 Iodo- and bromoarenes coupled efficiently at 30 °C to achieve 82-93% conversions in 20-30 min whereas chloroarenes required 1-1.5 h to obtain 42-52% conversions. This compares to only 25% conversion for the silent reaction at 25 °C. Significant homocoupling of the phenylboronic acid was reported when the reactions were... 

Tsunoyama, H., Sakurai, H., Ichikuni, N., Negishi, Y. and Tsukuda, T. (2004) Colloidal gold nanoparticles as catalyst for carbon-carbon bond Formation Application to aerobic homocoupling of phenylboronic acid in water. Langmuir, 20, 11293-11296. 

Pd nanoparticles supported on PANI-NFs are efficient semi-heterogeneous catalysts for Suzuki coupling between aryl chlorides and phenylboronic acid, the homocoupling of deactivated aryl chlorides, and for phenol formation from aryl halides and potassium hydroxide in water and air [493], PANl-NF-supported FeCl3 as an efficient and reusable heterogeneous catalyst for the acylation of alcohols and amines with acetic acid has been presented [494]. Vanadate-doped PANI-NFs and PANI-NTs have proven to be excellent catalysts for selective oxidation of arylalkylsulfides to sulfoxides under nuld conditions [412]. Heterogeneous Mo catalysts for the efficient epoxidation of olefins with ferf-butylhydroperoxide were successfully synthesized using sea urchin-Uke PANI hollow microspheres, constructed with oriented PANI-NF arrays, as support [495]. Pt- and Ru-based electrocatalyst PANI-NFs—PSSA—Ru—Pt, synthesized by the electrodeposition of Pt and Ru particles into the nanofibrous network of PANI-PSSA, exhibited an excellent electrocatalytic performance for methanol oxidation [496]. A Pt electrode modified by PANI-NFs made the electrocatalytic oxidation reaction of methanol more complete [497]. Synthesis of a nanoelectrocatalyst based on PANI-NF-supported... 

During the past two decades gold has attracted much attention due to its unique catalytic properties for numerous reactions [116,117]. Therefore, it has been shown that isolated and heterogenized Au"" ions (n = 1 or 3) are highly active in reactions such as the selective hydrogenation of 1,3-butadiene to butenes [ 118], the homocoupling of phenylboronic acid [119], or the selective isomerization of epoxides to allylic alcohols [120]. 

H. Tsunoyama, H. Sakurai, N. Ichikuni, Y. Negishi, T. Tsukuda, 2004, Colloidal Gold Nanoparticles as Catalyst for Carbon-Carbon Bond Formation Application to Aerobic Homocoupling of Phenylboronic Acid in Water, Langmuir, 20, 11293-11296. 

---