Isolation and characterization of [Fe2(CO)6Se2{μ-(CO)3Cr(η5-C5(H)(CH2Ph)(Ph)(OEt)}], [(CO)6Fe2{μ-EC(Ph)=C(E′)C(H)(OEt)}]2 and [(CO)6Fe2{μ-SC(H)(Ph)C(Te)=C(H)(OEt)}] from the thermolysis of Fischer carbene adducts [(CO)6Fe2EE′{μ-C(Ph)=C–C(OEt)=Cr(CO)5}] (E,E′=Se and E=S, E′=Te)

Thermolysis of the trimetallic adducts [(CO)6Fe2EE′{μ-C(Ph)=C–C(OEt)=Cr(CO)5}] 1a,b (1a: E=E′=Se; 1b: E=S, E′=Te) in refluxing THF yield the following complexes: [Fe2(CO)6EE′{μ-(CO)3Cr(η5-C5(H)(CH2Ph)(Ph)(OEt)}], (2: E=E′=Se); [(CO)6Fe2{μ-EC(Ph)=C(E′)C(H)(OEt)}]2, (3a: E=E′=Se; 3b: E=S, E′=Te) and [(CO)6Fe2{μ-EC(H)(Ph)C(E′)=C(H)(OEt)}], (4: E=S, E′=Te), where the product formation depends on the nature of chalcogen atoms present in the trimetallic adducts 1a and 1b. All products have been characterized by IR and 1H-, 13C-, 77Se- and 125Te-NMR spectroscopy and structural types were unequivocally established by X-ray crystallographic analysis of compounds 3a and 4.© Elsevie