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The hydrogenolysis of the Ar-Cl bond in chlorinated benzoic acids, anilines, and nitrogen-containing heterocycles by the action of NaH2PO2 in the presence of catalytic amounts of PdCl2 and NaOH in an aqueous medium was studied. Under these conditions aryl chlorides were quantitatively converted into the corresponding arenes. Chloropyridines, such as 2-chloropyridine and 3, 5-dichloropicolinic acid, did not undergo hydrogenolysis even in the presence of an equivalent amount of NaI. A distinctortho effect was observed forortho-substituted substrates.

The hydrogenolysis of the C-O bond in monoaryl sulfates by the action of an excess of NaH2PO2 in the presence of catalytic amounts of PdCl2 and KOH is studied. The reaction proceeds chemoselectively with complete ester conversion to the corresponding arenes.

A study was carried out on the electrophilic substitution reactions in benzene and toluene by the action of ClCH2OCH3 in the presence of trivalent lanthanide salts, LnCl3, where Ln=Ce, Dy, Er, and Sm(O3SCF3)3 as the catalysts, at room temperature over 24 h. These lanthanide salts display the properties of weak but hard Lewis acids. The reaction proceeds exclusively by chloromethylation with the subsequent formation of diarylmethanes.

A study was carried out on the electrophilic substitution reactions of benzene and toluene by the action of a mixture of an acyl halide and benzaldehyde in the presence of trivalent lanthanide salts LnCl3, where Ln=Ce, Dy, Er, Sm, Yb, and Yb(O3SCF3)3, as catalysts at 40‡C over 24 h. The reaction stops at the formation of the corresponding triarylmethane compounds. A mechanism was proposed for this reaction. Lanthanide salts were found not to catalyze the usual Friedel-Crafts acylation of arenes.