The reactions of iodobenzene with azole compounds, 1,2-disubstituted imidazoles and 2-substituted oxazoles and thiazoles, were examined in the presence of catalytic amounts of Pd(OAc)2 and PPh3 in DMF using alkali metal carbonates as bases. It was found that the coupling products, 5-arylazoles, could be selectively produced in good yields by using Cs2CO3. In the case that their 2-position is unsubstituted, the site could also be arylated. In reactions using bromobenzene in place of iodobenzene, K2CO3 was also as effective as Cs2CO3. The addition of a stoichiometric amount of CuI appeared to specifically promote the reactions of thiazoles as well as those of thiophene derivatives. The reactions of 2-unsubstituted azole compounds with aryl iodides could be mediated by CuI to some extent without using the palladium species to give 2-arylazoles.

N-(2‘-Phenylphenyl)benzenesulfonamides react with acrylate esters accompanied via cleavage of the C−H bond at their 2‘-position in the presence of a catalyst system of Pd(OAc)2 and Cu(OAc)2 and a base under air to produce 5,6-dihydro-5-(benzenesulfonyl)phenanthridine-6-acetate derivatives in high yields. The reactions of benzoic acid with butyl acrylate and styrene can also give 3-[(butoxycarbonyl)methyl]phthalide and 3-phenylisocoumarin, respectively.

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Cyclopentadiene and metallocenes, typically zirconocene dichloride, are suitable substrates for multiple arylations with aryl bromides in palladium-catalyzed reactions. Thus, various aryl bromides bearing either an electron-donating or an electron-withdrawing substituent can react with these substrates to afford the corresponding 1,2,3,4,5-pentaaryl-1,3-cyclopentadienes in a single preparative step. Derivatives of cyclopentadiene, including di- and trisubstituted cyclopentadienes, and indene are arylated in a similar fashion.

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