The formation of dimetallocycles from reactions of alkynes with (η-C"5Me"5)"2Rh"2(CO)"2; X-ray structure of [(η-C"5Me"5)"2Rh"2(η-CO) {μ-η^2,η^2-C(O)C"2-(CF"3)"2}] - S. Dickson, R.; S. Evans, G.; D. Fallon, G. (Elsevier)
The complexes (η-C"5Me"5)"2Rh"2(μ-CO) {μ-η^2,η^2-C(O)CRCR} are obtained from reactions between (η-C"5Me"5)"2Rh"2(CO)"2 and the alkynes RCCR (R CF"3, CO"2Me, or Ph) at 25^oC. The molecular geometry of the complex with R CF"3 has been established by X-ray diffraction; the bridging 'ene-one' unit adopts a μ-η^2,η^2 conformation. Other complexes isolated from these reactions include (η-C"5Me"5)Rh(C"6R"6) (R CF"3, CO"2Me), (η-C"5Me)"2Rh"2(C"4R"4) (R CO"2Me) and (η-C"5Me"5)"2Rh"2(CO"2C"2R"2) (R Ph). The reaction between (η-C"5Me"5)"2Rh"2(CO)"2 and C"6F"5CCC"6F"5 gives (η-C"5Me"5)"2Rh"2(CO)"2(C"6F"5C"2C"6F"5). Mononuclear complexes such as (η-C"5Me"5)Co(C"4R"4CO) are the major products isolated from reactions between (η-C"5Me"5)"2CO"2(CO)"2 and alkynes at 25^oC.
http://linkinghub.elsevier.com/retrieve/pii/S0022-328X(00)87086-2
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