INOR 850 |
| The activation of aryl, acyl and carbene ligands with heteroaryl substituents in binuclear group 6 and 7 transition metal complexes not only lead to diverse modes of coordination, but can also lead to novel transformations, regioselective reaction routes and unique modifications at one of the metal-ligand sites. In all instances the metals are in electronic contact via g-conjugation and charge delocalization. Complexes resulting from the reagents shown below will be used to demonstrate (i) metal exchange processes, (ii) electronic and steric factors in determining structural features of ligands, (iii) carbon-carbon coupling reactions, (iv) region-selective bensannulation reactions and (iv) carbene modifications facilitated by carbene oxidation. In ó,g-coordinated bimetallic complexes a preference for a particular coordination site was found and this was determined by the nature of the metal. On the other hand, ligand sites can also be manipulated by electronic and sterical factors. Carbon-carbon coupling reactions in biscarbene complexes lead to a variety of products because of a carbene ligand's sensitivity in biscarbene complexes towards reactions with unsaturated organic substrates, oxygen and water. Carbene ligands can be modified into aldehydes or esters depending on the reaction conditions and the nature of the transition metal. Sites for bensannulation are determined by the nature of the metal and the heteroatom in the substituent. This work has relevance in coordination chemistry and catalysis.
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Applications of Organometallic Chemistry
1:30 PM-4:40 PM, Wednesday, August 22, 2007 BCEC -- 205C, Oral
Division of Inorganic Chemistry |
