Nickel 2-ethylhexanoate aromatization

Ziegler catalysts prepared from nickel or cobalt 2-ethylhexanoate and triethylaluminum (3 or 4 1 ratio) are very efficient for the hydrogenation of aromatic compounds.o-Xylene (51) gives a mixture of cis- (52) and trans-1,2-dimethylcyclohexane (53) in 65 35 ratio. Phenol (54), dimethyl phthalate and dimethyl terephthalate are also reduced in high yield, while nitro-substituted benzene and phenols cannot be reduced. Catalytic activity toward benzene hydrogenation decreases in the order Ni > Co > Fe > Cr > Cu. ... 

With nickel(II) 2-ethylhexanoate and triethylaluminum, tetralin (59) is obtained by hydrogenation of naphthalene (55). Polycyclic aromatics, such as anthracene (57 equation 8), 9-methylanthracene and 9-trifluoroacetylanthracene, are partially hydrogenated to 1,2,3,4-tetrahydroanthracene derivatives by use of [Rh(DPPE)(arene)]+ in methanol and by ruthenium hydride complexes having triphenylphosphine ligands... 

Lapporte and Schuett prepared a catalyst which is extremely effective for the hydrogenation of aromatics by adding triethylaluminum to a solution of nickel (II) 2-ethylhexanoate in benzene or heptane. An exothermic reaction occurred with evolution of a gas which is greater than 95% ethane and production of a black, nonpyrophoric solution of a catalytically active complex. 

Nickel 2-ethylhexanoate/triethylalumiimm Ring hydrogenation of aromatics... 

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