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An improved protocol for the direct arylation of N-phenyl- N-benzyl(thiazol-2-yl)amine by using aryl bromides as aryl donors is reported. The procedure was compared with a previously reported protocol in which aryl iodides were used as arylating agents. The improved direct arylation protocol was applied to structurally isomeric and nonaromatic 3-benzyl- N-phenylthiazol-2(3 H)-imine. The two substrates for direct arylation were obtained from a common starting material, N-phenyl(thiazol-2-yl)amine, which was regioselectively benzylated either on the exo-cyclic or the endo-cyclic nitrogen by using two sets of reaction conditions. For the arylation of the isomeric nonaromatic 3-benzyl- N-phenylthiazol-2(3 H)-imine, exclusive regioselectivity in the 5-position could be achieved. [ABSTRACT FROM AUTHOR]

The direct arylation of benzo[ b]furan, benzo[ b]thiophene, and indole has been studied by using aromatic bromides as the aryl source. The protocol employing common reagents and a Pd catalyst has led to the regioselective arylation of these heterocycles at the 2-position. A range of functional groups were tolerated, providing quick access to a variety of arylated benzo-fused heterocycles that would be accessible more elaborately using classical synthetic strategies. This is the first systematic study of the direct arylation of benzo[ b]furan. [ABSTRACT FROM AUTHOR]

Polysubstituted imidazoles represent a common structur-al motif in bioactive molecules. A modular and flexible strategy to-wards 2,4,5-triarylated imidazoles is reported applying a Suzuki-Miyaura cross-coupling protocol. Employing 1-protected 2,4,5-tri-bromoimidazole as starting material, both stepwise and one-pot pro-tocols towards the title compounds are disclosed. The utility of the approach was demonstrated by synthesizing neurodazine, a biolog-ically active molecule affecting neuronal cell differentiation. [ABSTRACT FROM AUTHOR]

The direct arylation of N-(2-pyridyl) substituted anilines is described. Arylation takes place in ortho position to the amine functionality and is directed by the pyridine N-substituent. Remarkably, N-arylation was never observed as a competing process even though conditions also suitable for Buchwald-Hartwig reactions were applied. The scope of the reaction was investigated in terms of aryl donors as well as the electronic nature of the substrate. Good yields were obtained for most examples through an operationally simple procedure, which did not require inert conditions or even glove box techniques. Pd(OAc)2 was applied as a cheap catalyst and boronic acids as readily available aryl donors. To obtain full conversion, 1,4-benzoquinone and a silver salt (e.g., Ag2O) were required as additives and reacted at relatively mild temperatures (e.g., 80 °C). Additionally, the pyridine-directing group was cleaved after the reaction to give ortho-arylated aniline derivatives. [ABSTRACT FROM AUTHOR]

Two bites at the cherry: RecENt examples for the iron ‐ catalyzed direct functionalization of (hetero)aromatic CH bonds are presENted. The reactions highlighted herein report arylation, cyanation, and amination of various aromatic carbo ‐ and heterocycles. A common feature of these transformations is the bENeficial effect of bidENtate ligands. [ABSTRACT FROM AUTHOR]

A ruthenium(II)-catalyzed protocol for the direct arylation of benzylic amines was developed. Employing 3-substituted pyridines as directing groups, arylation was achieved using aryl bromides or aryl iodides as the aryl source. Potassium pivalate proved to be an important additive in this transformation. The arylation took place selectively in the benzylic sp3position, and no significant competitive sp2arylation was observed. Arylated imines were observed as byproducts in minor amounts. Additionally, reaction conditions for cleaving the pyridine group were established, enabling access to bis-arylated methylamines. [ABSTRACT FROM AUTHOR]

An abstract of the article "Aryl Bromides and Aryl Chlorides for the Direct Arylation of Benzylic Amines Mediated by Ruthenium(II)," by Navid Dastbaravardeh and colleagues is presented.

A highly efficient direct arylation process of benzylic amines with arylboronates was developed that employs Ru catalysis. The arylation takes place with greatest efficiency at the benzylic sp3 carbon. If the distance to the activating aryl ring is increased, arylation is still possible but the yield drops significantly. Efficiency of the CH activation was found to be significantly increased by use of 3-substituted pyridines as directing groups, which can be removed after the transformation in high yield. Calculation of the energy profile of different rotamers of the substrate revealed that presence of a substituent in the 3-position favors a conformation with the CH2 group adopting a position in closer proximity to the directing group and facilitating C-H insertion. This operationally simple reaction can be carried out in argon atmosphere as well as in air and under neutral reaction conditions, displaying a remarkable functional group tolerance. Mechanistic studies were carried out and critically compared to mechanistic reports of related transformations. [ABSTRACT FROM AUTHOR]

Abstract: The arylation of thiazoles in 4- and 5-position was investigated in detail. Suzuki–Miyaura and Stille cross-coupling reactions were tested using thiazoles either as halide or organometal species. The obtained results were critically compared to develop helpful guidelines for selection of the cross-coupling methodology with the best potential for good and reliable results for a given synthetic problem without the need for tedious optimization of reaction parameters. [Copyright &y& Elsevier]

An improved procedure is evaluated for the arylation of thiazoles of type (I) with aryl bromides which produce better yields in most cases compared with the corresponding iodides. [ABSTRACT FROM AUTHOR]

Suzuki-Miyaura coupling and arylation reactions of 2-phenylpyridine are performed by using continuous flow conditions. [ABSTRACT FROM AUTHOR]

The mono-arylation in α-position of saturated cyclic amines is presented. [ABSTRACT FROM AUTHOR]