From B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub> to B(OC<sub>6</sub>F<sub>5</sub>)<sub>3</sub>: Synthesis of (C<sub>6</sub>F<sub>5</sub>)<sub>2</sub>BOC<sub>6</sub>F<sub>5</sub>\nand C<sub>6</sub>F<sub>5</sub>B(OC<sub>6</sub>F<sub>5</sub>)<sub>2</sub> and Their Relative Lewis Acidity
George J. P. Britovsek (1338111)Juri Ugolotti (2393140)Andrew J. P. White (1310940)
Abstract
The pentafluorophenyl esters of bis(pentafluorophenyl)borinic acid (C<sub>6</sub>F<sub>5</sub>)<sub>2</sub>BOC<sub>6</sub>F<sub>5</sub> (<b>2</b>) and\npentafluorophenylboronic acid C<sub>6</sub>F<sub>5</sub>B(OC<sub>6</sub>F<sub>5</sub>)<sub>2</sub> (<b>3</b>) have been prepared and characterized by\nmultinuclear NMR and X-ray analysis. VT NMR studies have shown that restricted rotation\naround the B−O bond in <b>2</b> occurs below 193 K, corresponding to Δ<i>G</i><sup>⧧</sup> = 35 kJ/mol for this\nprocess. This low barrier and the random torsion angles around the B−O bonds observed in\nthe solid state structures of compounds <b>2</b>, <b>3</b>, and B(OC<sub>6</sub>F<sub>5</sub>)<sub>3</sub> (<b>4</b>) suggest that these torsion\nangles are not related to pπ−pπ interactions between boron and oxygen, but more likely a\nconsequence of the extensive intermolecular F−π interactions seen in the solid state\nstructures. The Lewis acidity of <b>2</b>, <b>3</b>, and <b>4</b> has been compared with B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub> (<b>1</b>), using\nvarious Lewis bases. All compounds <b>1</b>−<b>4</b> appear to be strong Lewis acids, whereby <b>4</b> interacts\nmore strongly with hard bases whereas <b>1</b> binds more strongly to softer bases.
Metrics
Topics
Related Documents
Xenon(IV)–Carbon Bond of [C<sub>6</sub>F<sub>5</sub>XeF<sub>2</sub>]<sup>+</sup>; Structural Characterization\nand Bonding of [C<sub>6</sub>F<sub>5</sub>XeF<sub>2</sub>][BF<sub>4</sub>], [C<sub>6</sub>F<sub>5</sub>XeF<sub>2</sub>][BF<sub>4</sub>]·2HF, and [C<sub>6</sub>F<sub>5</sub>XeF<sub>2</sub>][BF<sub>4</sub>]·<i>n</i>NCCH <sub>3</sub> (<i>n</i> = 1, 2); and the Fluorinating Properties of [C<sub>6</sub>F<sub>5</sub>XeF<sub>2</sub>][BF<sub>4</sub>]
Karsten Koppe (2126239)Jamie Haner (1831111)Hélène P. A. Mercier (2126242)Hermann-J. Frohn (2126236)Gary J. Schrobilgen (1505116)
Reaction of V(C<sub>6</sub>H<sub>6</sub>)<sub>2</sub> with the Borane Adducts of Malononitrile\n[(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>B·NCCH<sub>2</sub>CN·B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>] and Water [H<sub>2</sub>O·B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>]
Robert Choukroun (2414704)Christian Lorber (736495)Laure Vendier (1347666)
Reaction of V(C<sub>6</sub>H<sub>6</sub>)<sub>2</sub> with the Borane Adducts of Malononitrile\n[(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>B·NCCH<sub>2</sub>CN·B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>] and Water [H<sub>2</sub>O·B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>]
Robert Choukroun (2414704)Christian Lorber (736495)Laure Vendier (1347666)
Comparative Lewis Acidity\nin Fluoroarylboranes: B(<i>o</i>‑HC<sub>6</sub>F<sub>4</sub>)<sub>3</sub>, B(<i>p</i>‑HC<sub>6</sub>F<sub>4</sub>)<sub>3</sub>, and B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>
MatthewM. Morgan (2003758)Adam J. V. Marwitz (2003755)Warren E. Piers (1569994)Masood Parvez (1569997)
Syntheses and Characterization of W(NC<sub>6</sub>F<sub>5</sub>)F<sub>5</sub><sup>–</sup> and W<sub>2</sub>(NC<sub>6</sub>F<sub>5</sub>)<sub>2</sub>F<sub>9</sub><sup>–</sup> Salts and Computational Studies of the W(NR)F<sub>5</sub><sup>–</sup> (R = H, F, CH<sub>3</sub>, CF<sub>3</sub>, C<sub>6</sub>H<sub>5</sub>, C<sub>6</sub>F<sub>5</sub>) and W<sub>2</sub>(NC<sub>6</sub>F<sub>5</sub>)<sub>2</sub>F<sub>9</sub><sup>–</sup> Anions
Douglas Turnbull (271094)Stacey D. Wetmore (696456)Michael Gerken (2078125)