C-H and N-H activation by Pt(0) in N- and O-heteroaromatic compounds

The reactions of [Pt(PEt₃)₄] with various azoles afforded platinum(II) hydride complexes of the type trans-[PtH(1-azolyl)(PEt₃)₂], where azolyl=indolyl (1), imidazolyl (2), benzimidazolyl (3), pyrazolyl (4) and indazolyl (5), by oxidative insertion of the metal centre into the N-H bonds of the respective azoles. Pyrrole was much less reactive. Complexes trans-[PtH(R)(PEt₃)₂], where R=2-furyl (6), 2-benzoxazolyl (7) and 2-benzothiazolyl (8) were prepared via C-H bond activation. For benzothiazole, insertion into the C-S bond did not occur. Analogous C-H activation products with 1-methylpyrrole and dibenzofuran could not be isolated.     

Über Chalkogenolate. 167. Untersuchungen über 1,2-Hydrazin-bis(monothioformiate)

On Chalcogenolates. 167. Studies on 1,2-Hydrazine-bis(monothioformates) Hydrazine reacts with COS in the presence of sodium methoxide to produce Na₂[SOC? ;NH? ;NH? ;COS]. It forms with methyl iodide the S,S′-dimethyl ester. The compounds have been investigated by means of infrared, nuclear magnetic resonance, and mass spectra. The reaction of H₃CS? ;CO? ;NH? ;NH? ;CO? ;SCH₃ with Lawesson reagent yields 2,5-dimethylthio-1,3,4-thiadiazole .     

Interfacial interactions and structure of polyolefins

The elucidation of structural aspects of polyolefins (isotactic and syndiotactic polypropene and isotactic poly(1-butene)) oriented by epitaxial crystallization is briefly described. Investigations are performed by a combination of electron and Atomic Force Microscopy. AFM helps assess submolecular details in well defined crystallographic planes selected via the epitaxial crystallization.