Palladium-catalyzed cross-dehydrogenative coupling between anilides and aromatic aldehydes was achieved under aqueous conditions. A wide variety of the desired benzophenone derivatives was isolated in good to excellent yield. The reaction rate acceleration effect of acid and detergent has been demonstrated. Mechanistic insight has been obtained from quantum chemical calculations.Transition metal-catalyzed direct C À H bond functionalization is one of the most important transformations in recent organic synthetic strategies. [1] Although catalytic transformations based on palladium catalysts are the most frequently utilized oxidative coupling methods in organic syntheses, these reactions usually require harsh conditions (high temperature, long reaction time, necessity of inert atmosphere). Therefore the development of efficient palladium-catalyzed oxidative couplings based on highly active catalyst systems under mild reaction conditions is still highly demanded. Regarding the mechanisms of palladium-catalyzed transformations the presence of monometallic palladium complexes in the catalytic cycle is well accepted. [2] However, very recently the special role and activity of bimetallic palladium species has been discovered and demonstrated in several coupling reactions involving a C À H functionalization step. [3] Be-sides the assessment of the synthetic potential of bimetallic complexes in organic chemistry, a thorough understanding of their working mechanism is also essential. [4] There are several applications of palladium-catalyzed oxidative transformations for the formation of new carbon-carbon bonds via functional group-directed ortho-substitution. [5] Very recently, the synthesis of aromatic ketones from phenylpyridines [6] or acetanilides [7] could be achieved by the palladium-catalyzed oxidative coupling of aldehydes [8] including a C À H activation step.The recently described methodologies of Zhou, [7a] Kwong [7b] and Yu [7c] enable the transformation in toluene at 120 8C, 90 8C, and 40 8C, respectively (Scheme 1.). The latter procedure provides the most efficient conditions for the desired coupling due to the relatively short reaction time under the applied conditions (40 8C, 3 h). Utilization of ketocarboxylic acids instead of aldehydes enables the formation of benzophenone derivatives in a similar palladium-catalyzed coupling at room temperature as it was demonstrated by Ge and co-workers. [9] This transformation works efficiently at room temperature and it has excellent functional group tolerance.It is of note, amongst the previous methodologies depicted on Scheme 1., that only Kwongs proce-A C H T U N G T R E N N U N G dure [7b] offers possibilities for the transformation of ortho-substituted acetanilides.Palladium-catalyzed oxidative coupling of acetanilides with aromatic aldehydes results in 2-acylacetanilides and 2-aminobenzophenone derivatives after hydrolytic cleavage of the amide bond, which are impor-

A novel method for the ortho alkylation of acetanilide and aromatic urea derivatives via C-H activation was developed. Alkyl dibenzothiophenium salts are considered to be new reagents for the palladium-catalyzed C-H activation reaction, which enables the transfer of methyl and other alkyl groups from the sulfonium salt to the aniline derivatives under mild catalytic conditions.

A new mild, practical method for the synthesis of aminobenzophenone derivatives through the palladium catalyzed cross-dehydrogenative coupling of anilines with aldehydes in water-SDS mixture is reported. The method involves the protection of aniline followed by its oxidative coupling with the aldehyde and finally the removal of the protecting group in one pot, under aqueous conditions. With these two or three-steps sequences in hand, several Nacetyl and unprotected aminobenzophenone derivatives were isolated in good to excellent yield.Oxidative C -H bond activation is one of the most important topics in recent synthetic organic chemistry.

Mild Palladium-Catalyzed Oxidative Direct ortho-C-H Acylation of Anilides under Aqueous Conditions. -The rate accelerating effect of long chain anionic detergent and trifluoroacetic acid under aqueous conditions is shown. -(SZABO, F.; DARU, J.; SIMKO, D.; NAGY, T. Z.; STIRLING, A.; NOVAK*, Z.; Adv. Synth. Catal. 355 (2013) 4, 685-691, http://dx.doi.org/10.1002/adsc.201200948 ; Inst. Chem., Eoetvoes Lorand Univ., H-1117 Budapest, Hung.; Eng.) -G. Mueller 32-079

Synthesis, temperature‐dependent NMR structure investigation and utilization of a new, stable and easily accessible aryl‐diadamantylphosphine ligand family is reported. The bulky and electron‐rich phosphorus center of the ligand enhances the catalytic activity of palladium in cross‐coupling reactions of sterically demanding ortho‐substituted aryl halides. In our study, we demonstrated the synthetic applicability of the new phosphine ligands in Buchwald‐Hartwig and tosyl hydrazone coupling reactions.