Properties of Diene Complexes

Stable complexes containing 1,3-dienes are known for many transition metals of groups 3-10. The central atoms have d -d electronic structures. Generally, these compounds are quite air stable, are easily soluble in organic solvents, and, after heating. 

Usually, 1,3-diene compounds constitute 18 complexes. However, exceptions are known these comprise square-planar 16e complexes possessing electronic configuration of the central atom. 

Bis(butadiene)carbonylmanganese, [Mn(C4H6)2 (CO)], is a lie paramagnetic compound with the magnetic moment corresponding to one unpaired electron. 

Organometallic Compounds, The Transition Elements, Methuen, London (1968). 

Streitwieser, Jr., Molecular Orbital Theory for Organic Chemists, Wiley, New York (1961). 

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