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)

Abstract

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.