Alkenes acetylacetone metal complexes

As shown by Breslow et al. during the mid-1960s, most transition-metal alkox-ide or acetylacetonate complexes catalyze the hydrogenation of alkenes in the presence of an activator (Table 6.19) [5]. Other precursors have been used such as [CpCr(CO)3]2, but it is more difficult to understand how the active species are formed [133]. 

Some transition metal chelates, such as Mn(II), Co(II), Ce(IV), Fe(III), or Cu(II) acetylacetonates, initiate polymerization of alkenes at wide temperature range 25-100°C, depending on monomer and solvent, which both can affect the stability of the complexes. 

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