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A series of new (tricarbonyl)rhenium(I) complexes were synthesized using chiral bidentate ligands (+)/(-)-iminopyridines (L R /L S ). The reaction yielded a mixture of mononuclear Re(I) diastereoisomers, formulated as fac -[Br(CO) 3 Re ( S / R ) L ( S / R ) ]. Each single diastereoisomer was isolated and fully characterized. X-ray crystallography and circular dichroism spectra verified their enantiomeric nature. The cytotoxicity of each complex was evaluated against six cancer cell lines. The effect of the two complexes on viability, proliferation, and migration was analyzed on glioblastoma cell lines (U251 and LN229). Changes in the expression of histones, apoptotic, and key signaling proteins, as well as alterations in DNA structure, were also observed. These experiments showed that the chirality associated with both metal and ligand has a strong influence on cytotoxicity.

An unprecedented C-benzylation rearrangement reaction, catalyzed by palladium, is reported. The reaction proceeds by rearrangement leading to the direct synthesis of para or ortho benzyl-substituted N-methylanilines. The product is obtained in high regioselectivity, without the need to use a ligand for the catalytic process., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A simple and regioselective synthesis of phenoxy esters and phenylthio esters is reported. The products are obtained by selective alkoxycarbonylation catalyzed by Pd2(dba)3, 1,4-bis(diphenylphisphino)butane (dppb), and syngas (CO/H2) in chloroform/alcohol. This methodology affords bifunctional products in good yield with excellent n-selectivity and without the need to use additives.

The phosphine ligand mediated palladium catalyzed alkoxycarbonylation of alkenes was investigated with the objective of attaining good linear selectivity for the ester. The effect of various parameters such as solvents, additives, palladium precursors, CO pressures, and alkenes of various structural complexities were examined. The results revealed the importance of using a Lewis acid such as SnCl2 or Ti(O(i)Pr)4 in combination with a monodentate ligand such CYTOP 292 or P(p-anisyl)3 to enhance the regioselectivity for the linear isomers in the range of 70-96%.

A simple, efficient, and regioselective synthesis of 3-methyl-3,4-dihydrocoumarins is reported. The reaction of 2-allyl phenols with synthesis gas was catalyzed by PdI2, and 1,3,5,7-tetramethyl-6-phenyl-2,4,8-trioxa-6-phosphaadamantane (L1) and 1,3,5,7-tetramethyl-6-tetradecyl-2,4,8-trioxa-6-phosphaadamantane (L2) were effective as ligands, affording good product selectivity in all cases.

The title compound, C(18)H(27)NO(2), crystallizes as the enamine form with Z geometry. The β-enamino-ester fragment forms a dihedral angle of 87.5 (1)° with the isopropyl-phenyl frame. The structure exhibits an intra-molecular N-H⋯O hydrogen bond. In addition, in the crystal, mol-ecules are linked by a centrosymmetric inter-molecular N-H⋯O hydrogen bond.

The title compound, C(15)H(21)NO(2), was obtained by the reaction of acetoacetate with 2,4,6-trimethyl-aniline using Mexican bentonitic clay as a catalyst. It crystallizes in the enamine form. The β-enamino ester residue is almost perpendicular to the aromatic ring [dihedral angle = 88.10 (6)°]. The mol-ecular conformation is stabilized by a strong intra-molecular N-H⋯O hydrogen bond. In addition, the N-H group forms a weak inter-molecular N-H⋯O hydrogen bond linking the mol-ecules into centrosymmetric dimers.