Rhodium-carbon dioxide complex, coordination

Albano P, Aresta M, Manassero M (1980) Interaction of carbon dioxide with coordinatively unsaturated rhodium(I) complexes with the ligand 1,2 bis(diphenylphosphino)ethane. Inorg Chem 19(4) 1069-1072... 

In recent years, interest has intensified in the chemistry of carbon dioxide, stimulated by the current concern about alternate petrochemical feedstocks. One area under active exploration involves C02 activation via coordination to a transition metal complex.1 Several adducts of C02 have been claimed, and two monometallic complexes, with x-ray structures which have been published, are shown below schematically (1 and 2).2,3 We report here two examples of the preparation of 1 1 C02 adducts of a series of rhodium and iridium complexes and, relatedly, methods for preparing the 2 1 C02 lr complex 2. 

So far no definite carbon dioxide insertion into analogous metal carbon bonds has been reported. A rhodium complex coordinated with carbon dioxide was reported by Iwashita and Hayata 122>. 

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