Effect of cross-conjugation on properties of α-mercurated carbonyl compounds

Conclusions The polarographic data and the data of the IR spectra of the-mercurated esters of the cinnamic and crotonic acids show that in these compounds the- conjugation of the C-Hg bond with the C=O group is weakly expressed, and may be completely absent.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1912–1913, August, 1973.     

The Effect of Substituents at the Phosphorus Atom on the Equilibrium Position in the Tautomeric Phosphoryl-Hydroxy-Ylide Triad Systems

Abstract

By means of NMR and IR spectroscopy there has been established that the equilibrium position in the phosphoryl-hydroxyylide prototropic systems /I-V/ depends on the nature of substituents at the phosphorus atom.     

Elgctron Density Distribution and Intramolecular Dynayics in Phosphorane (Cl3C)2PCl3

Abstract

The trigonal-bipyramidal structure of phosphorane (Cl₃C)₂PCl₃ (I) with two non-equivalent axial Cl₃C-groups at the P atom was established by the X-ray diffraction method. At 293°K these groups are involved in independent libration around the longest molecular axis and some characteristics of these motions were estimated from diffraction data. Electron density distribution in I was studied at 153°K (λMo, ca. 7000 reflections, “high-angle” refinement to R=0.027 using 1310 reflections with sinθ/λ ≥ 0.70 A°^?1). At low temperature tile above-mentioned independent librations of the Cl₃C-groups become frozen, which is proved by the rigid-body analysis of the anisotropic thermal parameters of I, and also by the NQR ³⁵Cl spectral data. All chemical bonds in I are characterized by peaks of positive deformation electron density (DED). Positive DED peaks are also found near C1-atoms and attributed to the lone pairs of C1-atoms. Elongation of the P-C bonds (2.000 (2) and 1.992 (2) A°) is caused by electrostatic repulsion of the positively charged P and C atoms, whose charges were estimated from diffraction data. The character of the electron density distribution in I is in accordance with the generally accepted notion on the nature of chemical bonds in pentacovalent phosphoranes.     

Synthesis and Ldasic Properties of O,O,O-Triethyl-N-(2-Pyridyl) Imidophosphates

Abstract

The phosphorus (111) compounds are known to react readily with arylazides resulting in the formation of imi-dophosphorus compounds (Staudinger reaction)¹.

We nave obtained O,O,O-triethyl-Ii-(2-pyridyl)imido-pnosphates by the reaction of triethylphosphites with 2-pyridylazides (existing as tetrazoles) with a good yield.     

The Structure of o-Hydroxyaryloxy-bis-(o-arylenedioxy)-phosphoranes and their Acid-Base Properties

Abstract

The crystalline phosphoranes have been obtained. IR-, UV- and NMR spectra of phosphoranes (Ia,b) and their interaction products with nitrogen bases have been investigated. It was determined that phosphoranes have structure (I) with pentacoordinate phosphorus and phenolic hydroxy group, while their products of interactions with nitrogen bases have the ionic structure (II) with hexacoordinate phosphorus (II). The X-ray difraction approves the structure (I) for phosphorane Ib.     

The Structure of Adducts of Phosphoryl Compounds with Nitric Acid

Abstract

The sctructure of adducts of phosphoryl compounds with HNO₃ has been studied by means of IR spectra, thermometric titration and X-ray diffraction.