Abstract: A method of preparing an alkyl-substituted aromatic hydrocarbon, which comprises alkylating an aromatic hydrocarbon with an olefin in the presence of a catalyst comprising an iridium compound having at least one iridium atom and at least one &bgr;-diketonato ligand to produce the alkyl-substituted aromatic hydrocarbon.

Abstract: A method of preparing an alkyl-substituted aromatic hydrocarbon, which comprises alkylating an aromatic hydrocarbon with an olefin in the presence of a catalyst comprising an iridium compound having at least one iridium atom and at least one &bgr;-diketonato ligand to produce the alkyl-substituted aromatic hydrocarbon.

Abstract: This invention relates generally to the field of chemical synthesis, and more specifically, to the field of oxidative coupling of olefinic compounds and aromatic compounds, to produce olefinically substituted aromatic compounds. More particularly, this invention relates to methods for oxidative coupling of olefinic compounds and aromatic compounds which employ a rhodium(III) acetylacetonate catalyst and a copper(II) redox agent in a reaction medium which does not comprise a carboxylic acid component. In one embodiment, this invention pertains to methods for the preparation of styrene by the oxidative coupling of ethylene (an olefinic compound) and benzene (an aromatic compound), in the presence of Rh(acac).sub.2 Cl(H.sub.2 O), as catalyst, and Cu(II)(CH.sub.3 COO).sub.2, as copper(II) redox agent, in which benzene is both a reactant and the reaction medium.