David R. Manke

Titanium bis(alkylamido)phenylborane complexes

Abstract The bis(tert-butylamido)phenylborane ligand [tBuNBPhNtBu], may be delivered to titanium from its dilithio salt. Complexes containing a single chelating boradiamido ligand, [tBuNBPhNtBu]TiX2, (X=NMe2 (1), Cl (2), Bn (3)), have been prepared and characterized by 1H and 11B NMR, and single crystal X-ray structure analysis (2,3).

Amalgamating 4′-substituted 4,2′:6′,4′′-terpyridine ligands with double-helical chains or ladder-like networks

The reaction of five 4,2′:6′,4′′-terpyridine ligands containing diverse 4′-substituents with Hg(NCS)2 by layering methods afforded crystals of five novel HgII-based coordination polymers (1–5) that have been structurally characterized by both powder and single-crystal X-ray diffraction analysis. Similar one-dimensional (ID) polymeric chains were observed in the structures of polymers 1–3 where HgII serves as a mononuclear node to link ligands in a linear mode. All 1D chains in these complexes form double-helical structures through significant inter-chain π-stacking interactions, whereas the packing modes were slightly different in the three compounds, resulting from the influence of 4′-substituents. It was interesting to note that the structures of isomorphic 4 and 5 are completely different from those in 1–3. In the former cases, 1D ladder-like architectures that are assembled through the bridging thiocyanate groups were revealed, while remaining the extra 4′-pyridyl units non-coordinated.

The elastic constants of rubrene determined by Brillouin scattering and density functional theory

The linear elastic stiffness tensor of the crystalline organic semiconductor, rubrene, is measured using Brillouin light scattering spectroscopy and computed from first-principles van der Waals density functional theory calculations. Results are compared with recent measurements of in-plane reduced elastic constants c¯22, c¯33, and c¯23 determined through anisotropic buckling experiments.

Crystal structure of 3,4-di­meth­oxy­phenol

The title compound, C8H10O3, has two planar molecules in the asymmetric unit possessing mean deviations from planarity of 0.051 and 0.071 Å. In the crystal, there are two distinct infinite chains, both along [010]. The chains are formed by O—H⋯O interactions between the phenol and both the 3-methoxy and the 4-methoxy groups.

Crystal structure of 4-amino-2,6-di-chloro-phenol.

The title compound, C6H5Cl2NO, has a single planar molecule in the asymmetric unit with the non-H atoms possessing a mean deviation from planarity of 0.020 Å. In the crystal, O—H⋯N hydrogen bonds lead to the formation of infinite chains along [101] which are further linked by N—H⋯O hydrogen bonds, forming (010) sheets.

Crystal structure of 2,6-dimethyl-4-pyridone hemihydrate

The title compound (systematic name: 2,6-dimethyl-1H-pyridin-4-one hemihydrate), C7H9NO·0.5H2O, has a single planar molecule in the asymmetric unit with the non-H atoms possessing a mean deviation from planarity of 0.021 Å. There is also half of a water molecule present in the asymmetric unit. In the crystal, infinite (001) sheets are formed by N—H⋯O and O—H⋯O hydrogen bonds.

Dimethyl 2,2′-di­nitro­biphenyl-4,4′-di­carboxyl­ate

The title compound, C16H12N2O8, exhibits two near-planar aromatic ester groups with aryl–ester dihedral angles of 2.1 (2) and 4.2 (3)°. The dihedral angle between the aromatic rings is 58.0 (1)°. The two nitro groups are tilted slightly from the plane of the aromatic rings, making dihedral angles of 14.1 (1) and 8.2 (2)°. In the crystal, molecules are connected by weak C—H⋯O interactions, forming a three-dimensional network.

Cobalt(II) Coordination Polymer as a Precatalyst for Selective Hydroboration of Aldehydes, Ketones, and Imines

Highly effective hydroboration precatalyst is developed based on a cobalt(II)-terpyridine coordination polymer (CP). The hydroboration of ketones, aldehydes, and imines with pinacolborane (HBpin) has been achieved using the recyclable CP catalyst in the presence of an air-stable activator. A wide range of substrates containing polar C═O or C═N bonds have been hydroborated selectively in excellent yields under ambient conditions.

The crystal structures of iron and cobalt pyridine (py)–sulfates, [Fe(SO4)(py)4]n and [Co3(SO4)3(py)11]n

The crystal structures of two first-row transition metal (Fe and Co) pyridine–sulfate complexes are presented. The compounds demonstrate infinite chains of metal pyridine units connected by bridging sulfate anions.

Crystal structure of N,N,N-tris-[(1,3-benzo-thia-zol-2-yl)meth-yl]amine.

The title compound, C24H18N4S3, exhibits three near planar benzothiazole systems in a pseudo-C 3 conformation. The dihedral angles between the planes of the benzothiazole groups range from 112.56 (4) to 124.68 (4)° In the crystal, molecules are connected to each other through three short C—H⋯N contacts, forming an infinite chain along [100]. The molecules are also linked by π–π interactions with each of the three five-membered thiazole rings. [inter-centroid distance range: 3.614 (1)–4.074 (1) Å, inter-planar distance range: 3.4806 (17)–3.6902 (15) Å, slippage range: 0.759 (3)–1.887 (3) Å].