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A general method is developed for in situ trapping of arylmetal intermediates by halogen, sulfur, ketone and aldehyde electrophiles, which has produced the functionalization of the most acidic position in arene. [K.sub.3]P[O.sub.4] base is used for functionalizing pentafluorobenzene, benzothiazole and benzoxazole.

The development a palladium-catalyzed benzamide sequence ortho-arylation/rection with [(C[F.sub.3]CO).sub.2]O for convenient one-pot synthesis of ortho-arylated benzonitriles and fluorenone derivatives is reported. The N-propyl benzamides is converted to fluorenones while N-cyclohexyl benzamides yield benzonitrile derivatives.

A study conducted demonstrates that anilides possessing a number of different acyl groups could be arylated by aryl iodides by using palladium catalysis. The arylation products could be converted to phenanthridines by the reaction with trifluoroacetic anhydride.

The dual activation method using magnesium bromide (MgBr2) and a tertiary amine activated the hindered pivalic anhydride and converted it into a pivalate ester in 99% yield after 22 hrs. at room temperature. The amine and MgBr2 were mixed with linalool prior to reaction with the anhydride to minimize decomposition of the enolizable anhydride. Phthalic anhydrides and 1-methylcyclohexanol gave the highest yield although the reaction was slower than the corresponding benzoylations.

N -Aminopyridinium ylides are used as monodentate directing groups for copper-promoted C-H/N-H coupling of sp 2 C-H bonds with pyrazoles, imidazoles, and sulfonamides. Reactions proceed in fluorinated alcohol solvents at elevated temperatures and require use of 1.3-3 equiv of copper(II) acetate. This appears to be the first method for copper-promoted C-H/N-H coupling directed by a removable monodentate auxiliary in absence of added ligands.

3,5-Dimethylpyrazole was employed as a monodentate directing group for palladium-catalyzed ortho-sp 2 C-H arylation with aryl iodides. The reaction shows good functional group tolerance and outstanding selectivity for mono- ortho-arylation. Ozonolysis of ortho-arylated arylpyrazoles gave acylated biphenylamines that were further arylated to afford unsymmetrically substituted 2,6-diarylacetanilides.