New pyridyl-functionalized organoiron alkynyl complexes. Easy access to polymetallic architectures featuring an electroactive site by simple co-ordination reactions

The functionalized complexes 3a-d [(dppe)Cp*Fe(C=C-L)] (L = 4-Py, 3-Py, 2-P y) were isolated with good yields from the alkynyl complex 1 [(dppe)Cp*Fe(C =CH)1 (dppe = 1,2-bis(diphenylphosphino)ethane) from the corresponding brom opyridines using a Sonogashira-coupling reaction. These redox active compou nds are stable under two redox states and react as usual pyridyl ligands to wards methyl iodide or (THF)W(CO)(5). They allow easy access to the corresp onding pyridinium salt 4a or to the dimetallic iron-tungsten complex 5a. (C ) 1999 Elsevier Science S.A. All rights reserved.