Cyclometallation of amino-imines on palladium complexes. The effect of the solvent on the experimental and calculated mechanism.

The ortho-metallation reaction of chloro and acetato complexes of palladium(ii) having 5- and 6-membered kappa(2)-(N(amino),N(imino)) chelate ligands, [Pd(Me(2)NCH(2)(CH(2))(n)NCH(4-ClC(6)H(4)))(X)(2)] (X = AcO, Cl; n = 1, 2), in methanol solution has been carried out. The results are a good indicator of the distinct nature of the transition state involved in the processes where acetic acid has been used as a solvent. The presence of Brønsted bases, contrary to what has been reported for Pt(II) analogue compounds, does not affect this process, which indicates the "coordinated" nature of the leaving [H(+)] species.

New approach to the stereoselective synthesis of tertiary methyl ethers.

The Lewis acid-mediated addition of titanium enolates from 1 to dimethyl ketals of aliphatic methyl ketones followed by removal of the chiral auxiliary furnishes enantiomerically pure derivatives containing a tertiary methyl ether and a contiguous stereocenter in a straightforward manner.

Stereocontrolled synthesis of highly functionalized quaternary carbon centers: a route to alpha-substituted serines.

Three in a row! Highly functionalized quaternary amino polyols with three consecutive asymmetric carbon centers have been prepared through tandem hydroboration of allene 1 and addition to an aldehyde (see scheme; Cy = cyclohexyl, TBDPS = tert-butyldiphenylsilyl, Ts = 4-toluenesulfonyl). This one-pot process provides access to advanced intermediates for the enantioselective synthesis of alpha-substituted serines.

Synthesis and characterization of metallomacrocyclic palladium(II) complexes with new hybrid pyrazole ligands. Diffusion NMR studies and theoretical calculations.

Three new 3,5-dimethylpyrazolic hybrid ligands N1-substituted by polyether chains and phenyl groups have been synthesized: 1,2-bis[4-(3,5-dimethyl-1H-pyrazol-1-yl)-2-oxabutyl]benzene (L1), 1,3-bis[4-(3,5-dimethyl-1H-pyrazol-1-yl)-2-oxabutyl]benzene (L2), and 1,4-bis[4-(3,5-dimethyl-1H-pyrazol-1-yl)-2-oxabutyl]benzene (L3). The reaction of these ligands with [PdCl(2)(CH(3)CN)(2)] gives two kinds of complexes, monomer or dimer, depending on the solvent. Monomeric chelated complexes [PdCl(2)(L)] [L = L1 (1), L2 (2), L3 (3)] are obtained when the solvent of the reaction is acetonitrile, whereas when the reaction takes place in tetrahydrofuran binuclear compounds [PdCl(2)(L)](2) [L = L1 (4), L2 (5), L3 (6)] are formed.

2D copper(II) complex built from N-methyl-1,3-diamino-2-propanolate and azide ligands: structure, magnetic, and DFT studies.

The synthesis, structural characterization, and magnetic behavior of a new 2D copper(II) compound with formula {[Cu2(mu-O2CMe)(mu-MedapO)(mu1,1-N3)2]n (CH3OH)n} 1, in which MedapOH is N-methyl-1,3-diamino-2-propanol is reported herein. 1 crystallizes in the triclinic system, space group P1, with unit cell parameters a = 6.688(5) A, b = 10.