Cobalt-Catalyzed C-H Acetoxylation of Phenols with Removable Monodentate Directing Groups: Access to Pyrocatechol Derivatives.

An efficient cobalt-catalyzed C-H acetoxylation of phenols has been developed by using PIDA (phenyliodine diacetate) as a sole acetoxy source to synthesize pyrocatechol derivatives for the first time. The key feature of this method is the use of earth-abundant metal cobalt as the green and inexpensive catalyst for the acetoxylation of C(sp2)-H bonds under neutral reaction conditions. Furthermore, the gram-scale reaction and late-stage functionalization demonstrated the usefulness of this method.

Palladium-catalyzed para-selective arylation of phenols with aryl iodides in water.

Highly para-selective palladium-catalyzed direct arylation of phenols with aryl iodides was demonstrated by taking advantage of the formal inverse direct arylation strategy. A series of 4-aryl phenols were synthesised by employing water as a "green" solvent under mild reaction conditions.

catena-Poly[{µ-N'-[2-(carboxylatomethoxy)benzylidene]-2-hydroxybenzohydrazidato}(methanol-κO)nickel(II)].

In the title compound, [Ni(C16H12N2O5)(CH3OH)] n , the unique Ni(II) ion is coordinated in a distorted octa-hedral environment by three O atoms and one N atom from a symmetry-unique ligand in the equatorial sites. Coordination of the axial sites is provided by an O atom of a symmetry-unique methanol ligand and an O atom of a carboxyl-ate group from a symmetry-related ligand, thus generating a one-dimensional polymer parallel to [010]. In the crystal, O-H⋯N hydrogen bonds and π-π inter-actions, with a centroid-centroid distance of 3.693 (2) Å, form a two-dimensional network parallel to (100). In addition, weak C-H⋯O and C-H⋯N hydrogen bonds complete a three-dimensional network. An intra-molecular O-H⋯O hydrogen bond is also observed.

2-[(3S)-5-Oxooxolan-3-yl]isoindoline-1,3-dione.

The oxolan-2-one ring in the title compound, C(12)H(9)NO(4), has an envelope conformation with the atom linking the two five-membered rings being the flap atom.

4-[Bis(1H-indol-3-yl)meth-yl]benzonitrile.

In the title mol-ecule, C(24)H(17)N(3), the didhedral angles formed by the mean planes of the indole ring systems and the benzene ring are 86.44 (7) and 86.96 (7)°. The dihedral angle between the two indole ring systems is 72.08 (6)°. In the crystal, inter-molecular bifurcated (N-H)(2)⋯N hydrogen bonds link mol-ecules into sheets lying parallel to (010).

catena-Poly[[zinc-µ-[2-(2-{[2-(2-hy-droxy-benzo-yl)hydrazinyl-idene]meth-yl}phen-oxy)acetato-(2-)]] monohydrate].

In the title compound, {[Zn(C(16)H(12)N(2)O(5))]·H(2)O}(n), the unique Zn(II) ion is coordinated in a distorted square-pyramidal environment by three O atoms and one N atom from a symmetry-unique ligand. A symmetry-related ligand provides an O atom from a carboxyl-ate group to complete the coordination in the apical site and generate a one-dimensional polymer parallel to [010]. In addition to an intra-molecular O-H⋯N hydrogen bond, inter-molecular O-H⋯O and weak C-H⋯O hydrogen bonds are observed within the one-dimensional structure.

N,N-Bis[2-(ethoxy-carbonyl-meth-oxy)-benzyl-idene]pyridine-2,6-dicarbohydrazide.

In the title compound, C(29)H(29)N(5)O(8), the ester group is disordered over two sites with site-occupancy factors of 0.91/0.09. The crystal structure is stabilized by inter- and intra-molecular hydrogen-bond inter-actions.