INOR 297 |
| The Lewis acid tris(pentafluorophenyl)borane [B(C6F5)3] is a very useful reagent in organometallic and organic catalysis. Modification of the aryl groups on boron can alter Lewis acidity and change reactivity. We have devised facile routes to derivatives of [B(C6F5)3] that exhibit different Lewis acidities and reactivity. The reaction of [B(C6F5)3] with small phosphines (PR3, R = Me, Ph) yields expected Lewis acid : base adducts. However, when more sterically demanding tertiary phosphines are employed (R = iPr, Cy) the phosphine attacks at the para position of one of the C6F5 rings on boron, forming the Zwitterionic species, R3P-C6F4-BF(C6F5)2. Similarly, bulky secondary phosphines (Mes2PH, tBu2PH) undergo the same reaction. These zwitterionic species can readily be converted to anionic phosphines, cationic boranes, and phosphino-boranes. The synthesis, structure, and reactivity of these compounds will be presented. |
|
Main Group
7:00 PM-10:00 PM, Sunday, 10 September 2006 Moscone Center -- Hall D, Poster
Division of Inorganic Chemistry |