Metal-Free Oxidative para Cross-Coupling of Phenols was written by Morimoto, Koji;Sakamoto, Kazuma;Ohnishi, Yusuke;Miyamoto, Takeshi;Ito, Motoki;Dohi, Toshifumi;Kita, Yasuyuki. And the article was included in Chemistry – A European Journal in 2013.Application In Synthesis of 2-(3,5-Dimethoxyphenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane This article mentions the following:
A broadly applicable oxidative cross-coupling reaction of phenols (at the para position) with various arenes is described to obtain biaryls, e.g., I. This versatile hypervalent-iodine(III)-induced oxidative coupling operates under mild reaction conditions without the use of expensive catalysts, and tolerates a diverse range of the arene coupling partners. As the phenol rapidly interacts with the iodine reagent, homo-coupling of the starting materials and over-oxidation of the coupling products are avoided. The reaction has the addnl. benefit of being free of metal catalysts and not requiring prefunctionalization of the starting materials. In the experiment, the researchers used many compounds, for example, 2-(3,5-Dimethoxyphenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (cas: 365564-07-4Application In Synthesis of 2-(3,5-Dimethoxyphenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane).
2-(3,5-Dimethoxyphenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (cas: 365564-07-4) belongs to ethers. The oxygen atom in ethers are more electronegative than carbon, thus the hydrogens which are alpha to the ethers are more acidic than the simple hydrocarbons. Electron-deficient reagents are also stabilized by ethers. For example, borane (BH3) is a useful reagent for making alcohols. Pure borane exists as its dimer, diborane (B2H6), a toxic gas that is inconvenient and hazardous to use. Borane forms stable complexes with ethers, however, and it is often supplied and used as its liquid complex with tetrahydrofuran (THF).Application In Synthesis of 2-(3,5-Dimethoxyphenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane
Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem