Osamu Niyomura

A facile synthesis of potassium selenocarboxylates and their oxidation with XeF2 to diacyl diselenides: An X-ray structural analysis of di(4-methoxybenzoyl) diselenide

Several potassium selenocarboxylates were synthesized in moderate to good yields by the direct reaction of acyl chlorides with potassium selenide. The potassium salts were readily oxidized with XeF2 to give diacyl diselenides in quantitative yields. The structure of di(4-methoxybenzoyl) diselenide was established by X-ray diffraction analysis. Intramolecular interactions between the carbonyl oxygen and the selenium that is connected to the opposite carbonyl group were observed.

Bis(phosphine)bis(tellurocarboxylato)-palladium(II) and -platinum(II) complexes: synthesis and crystal structure

Bis(phosphine)bis(tellurocarboxylato)-palladium(II) and -platinum(II), [M(RCOTe)2(PR′3)2] (Mxa0=xa0Pd or Pt; Rxa0=xa0But, Ph, 4-MeC6H4, etc.; R′xa0=xa0Et or Ph), were synthesized in moderate to good yields by treating sodium tellurocarboxylates or O-trimethylsilyl telluroesters with [MCl2(PR′3)2]. The platinum complexes with 2-methoxybenzenecarbotelluroato ligands also were synthesized from [Pt(PR′3)4] with the corresponding diacyl ditelluride. The tellurocarboxylato complexes are yellow to orange or red crystals, and labile thermally and toward oxygen. The nickel analogues [Ni(RCOTe)2(PR′3)2] (R′xa0=xa0Et or Ph) were obtained by similar fashion, but were too labile to isolate. X-Ray diffraction analysis of trans-[Pt(4-MeC6H4COTe)2(PEt3)2] was carried out, and compared with those of the corresponding thio- and seleno-carboxylato complexes. These complexes crystallized in the same space group (P21/c) and are isostructural having a square-planar co-ordination geometry with thio- or telluro-carboxylato ligands which are unidentate.