INOR 304 |
| It is well known that Lewis acids (LA) and Lewis bases (LB) react together to form simple LA : LB adducts. We have discovered that when steric congestion precludes quenching of the acid and base via adduct formation, alternative reactivity is observed. The reaction of the Lewis acidic borane [B(C6F5)3] with the sterically demanding Lewis basic phosphine [(Mesityl)2PH] results in nucleophilic aromatic substitution at the para position of one of the C6F5 rings on boron yielding the Zwitterionic species, [(Mesityl)2PH-C6F4-BF(C6F5)2] (1). Compound 1 is readily converted into the species [(Mesityl)2PH-C6F4-BH(C6F5)2] (2), via H for F exchange using Me2SiClH. Compound 2 thermally loses H2 to give the phosphino-borane [(Mesityl)2P-C6F4-B(C6F5)2] (3), which in turn reacts with one atmosphere of H2 at 25oC to give compound 2. Synthesis and structure of these compounds and mechanistic details of the H2 activation will be presented.
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Energy and Environmental Inorganic Chemistry
7:00 PM-10:00 PM, Sunday, March 25, 2007 Hyatt Regency Chicago -- Riverside Center, Poster
Sci-Mix
Division of Inorganic Chemistry |