Tris(pentafluorophenyl)boron is the chemical compound (C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>B. The molecule consists of three pentafluorophenyl groups attached in a "paddle-wheel" manner to a central boron atom; the BC<sub>3</sub> core is planar. It has been described as the “ideal Lewis acid” because of its versatility and the relative inertness of the B-C bonds. Related fluoro-substituted boron compounds, such as those containing B-CF<sub>3</sub> groups, decompose with formation of B-F bonds.
Originally the synthesis employed C<sub>6</sub>F<sub>5</sub>Li, but this reagent can detonate with elimination of LiF.
The most noteworthy property of this molecule is its strong Lewis acidity: stronger than BF<sub>3</sub> but weaker than BCl<sub>3</sub>. This property indicates that the electronegativity of the C<sub>6</sub>F<sub>5</sub> group and... Read More