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1.
Rapid addition of alcohols to 1,2,3-diazaphosphole 1 easily gave tricoordinatedphosphorus compounds,which were sulfurized to tetracoordinated phosphorus compounds.When ethylene glycol and aminoethanol were used separately to react with 1,the tricoordinatedphosphorus compounds which formed,rearranged to pentacoordinated phosphorus compoundsand the substituents at N_2 affected the rearrangement significantly.  相似文献   

2.
Conclusions A quantum chemical calculation of six molecules of tetracoordinated phosphorus and five molecules of pentacoordinated phosphorus by the CNDO method permitted an explanation of individual details of the mechanism of certain reactions of these compounds and the variation of their reactivity.Translated from Izvestiya Akademii Nauk SSSR, SeriyaKhimicheskaya, No. 11, pp. 2486–2490, November, 1973.  相似文献   

3.
Regularities of transmission of the effect of equatorial and axial substituents were established for a number of chlorine-containing organic compounds of pentatalent phosphorus using35Cl NQR spectra. The field constants of35Cl NQR frequencies of the chlorine atoms participating in the P−Cl bond were estimated for a series of tetrahedral phosphorus ions. The35Cl NQR frequencies of chlorine atoms in tetracoordinated ions of pentavalent phosphorus and in analogous isoelectronic silicon compounds are related by a linear dependence. Deceased Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 915–922, May, 1999.  相似文献   

4.
The survey summarizes modern methods of synthesis and reactivity of tetracoordinated phosphorus cage compounds containing one or more endocyclic P–C bonds (phosphine oxides, phosphinates and phosphonates, phosphatripticenes and others). Intramolecular cyclization reactions including electrophilic aromatic substitution with unsaturated organophosphorus compounds, reactions of P–H-derivatives with carbonyl compounds as well as cycloaddition reactions involving I–IV-coordinated phosphorus derivatives are considered.  相似文献   

5.
Conclusions Energies of formation of complexes of hydrogen fluoride with compounds of tetracoordinated phosphorus, charge transfers in complexing, and other characteristics of these reactions calculated by CNDO/2 methods agree well with the measured values.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 496–502, March, 1979.  相似文献   

6.
Exchange reactions of tetrathiophosphates with thiophosphoryl chloride were studied. The exchange of thiol groups between compounds with tetracoordinated phosphorus centers proceeds at 150–220°C and results in the formation of dialkyl trithiochlorophosphates and alkyl(aryl) dithiodichlorophosphates or their mixtures depending on the ratio of the reagents. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1815–1817, September, 1998.  相似文献   

7.
Abstract

Organophosphorus compounds containing a functional group in the a-position of the alkyl radical are of great interest in both theoretical fundamental investigations and for practical applications. Functionally substituted methyl-phosphonites and their derivatives, belonging to this broad class of organophosphorus compounds, are convenient objects for investigating mutual effects of trivalent phosphorus and a heteroatom, or functional groups attached to it in the a-position. They have also become key substances in obtaining new organophosphorus compounds. Functionally sub-stituted compounds of tetracoordinated phosphorus have been intensively investigated in recent years; rather convenient methods of synthesis of these compounds have been proposed and their properties have been studied in detail1. However, the corresponding compounds of tricoordinated phosphorus are not available or difficult to obtain. Recently we re-ported on the properties of halogen-substituted methylphos-phines and their derivatives2. The present paper is devoted to the synthesis and investigation of the reactivity of alkoxy-, dialkylamino- and carbonyl substituted methylphos-phonites and their derivatives. In synthesis of alkoxymeth-ylphosphonites and their analogs we were the first to use labile alkoxymethylmagnesium chlorides in the reactions with tricoordinated phosphorus acid chlorides3. Previously unknown dialkoxymethylphosphonites and their analogs were obtained from hypophosphorous acid and trialkylorthofor-mates. The process of esterification and dialkoxymethylat-ion of hypophosphorous acid, being dependent on a catalyst, proceeds in different ways and results in the formation of dialkoxymethylphosphonite structures  相似文献   

8.
Conclusions The UV and Raman spectra of phenyl and-styryl derivatives of phosphorus were investigated. The results agree with concepts regarding the insulating effect of tetracoordinated phosphorus atoms and participation in electron effects of the unshared pair of electrons of trivalent phosphorus in the excited state.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 722–724, March, 1972.The authors thank V. S. Galeev and S. S. Krokhina for supplying us with compounds synthesized by them.  相似文献   

9.
Abstract

Macrorings bearing hexacoordinated phosphorus atoms or (and) tetracoordinated boron atoms, have been prepared from condensation of phenyldichlorophosphane in presence of diethylamine, or (and) boric or phenylboronic acids with some polyphenols. Their structures-have been established by NMR, microanalysis and mass spectrometry. These compounds are constituted according to (1 + 1), (2 + 2) and (3 + 3) stoichiometry.  相似文献   

10.
The synthesis of (CF3)2AsCl2N(SiMe3)2 is reported. This compound has been characterized on the basis of an X-ray analysis. It has a trigonal bipyramidal geometry with axial chlorine atoms. Variable temperature 1H- and 19F-NMR data show no observable changes. In comparison to pentacoordinated phosphorus compounds the tendency to form tetracoordinated derivatives is strongly diminished in the case of arsenic compounds.  相似文献   

11.
Conclusions We determined the conformational free energy of a phenyl substituent on a tri- and tetracoordinated phosphorus atom in a 2,4,6-trimethyl-1,3,5-dioxaphosphorinane ring.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1911–1916, August, 1978.  相似文献   

12.
The reactions of alkoxydimethylsilyl cyanides with some tetracoordinated phosphorus chlorides and fluorides were investigated. It was shown that the investigated reactions are realized primarily with the replacement of two halogen atoms by functional groups. The transformations of the phosphorus acid cyanides obtained with metal fluorides were studied.For previous communication, see [1].Institute of Physiologically Active Substances, Russian Academy of Sciences, 142432 Chernogolovka. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 187–191, January, 1992.  相似文献   

13.
Abstract

A new adduct was isolated from the reaction of borane-dimethyl-sulfide complex and conjugate bases of spirophosphorane prepared from benzilic acid. In solution, it exists as equilibrium between a spirophosphorane and a tetracoordinated phosphorus compound bearing a phosphorus-boron bond.  相似文献   

14.
Conclusions The reactivity of ethyl esters of phosphonic and phosphinic acids containing a hydroxymethyl group at the phosphorus atom in their reaction with hydroxide anion is usually high as a consequence of intramolecular catalysis of the cleavage of the ester bond involving the ionized OH group. The spontaneous hydrolysis of these esters proceeds according to a mechanism analogous to that for other alkyl esters of tetracoordinated phosphorus acids.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2139–2140, September, 1985.  相似文献   

15.
The coordination number of sulfur is used in this review as a classification principle; cyclic sulfur-nitrogen compounds in which the sulfur is di-, tri-, and tetracoordinated are discussed. Compounds with sulfur (and nitrogen) of coordination number 2 are electron-rich combinations of elements whose π-electrons are extensively delocalized. A correlation between the coordination number and the bond length can be observed in certain compounds containing tri- and tetracoordinated sulfur.  相似文献   

16.
Abstract

The Kabachnic-Fields reaction is one of the most important methods of synthesis of functionally substituted derivatives of tetracoordinated phosphorus with P-C bond. At the same time mechanism of this important and interesting reaction practically has not been investigated.  相似文献   

17.
The reactions of S-trimethylsilyl esters of dithiophosphoric, diamidodithiophosphoric, aryldithiophosphonic, aryltrithiophosphonic, and arylamidodithiophosphonic acids with diethyl acetal of benzaldehyde and ortho formiate and acetate were studied. On the basis of these studies, new derivatives of tetracoordinated phosphorus thioacids were obtained.  相似文献   

18.
Abstract

C-phosphorylation of pyrrole, furan, thiophene derivatives and their benzanalogs by phosphorus tribromide has been studied. Perspective methods for involving trivalent phosphorus residues at a different position of the rings have been developed. Unknown early the heterocycle's derivatives with tri- and tetracoordinated phosphorus substituents (1–5) and novel types of phosphoruscontaining heterocycles (6,7) have been obtained.  相似文献   

19.
Conclusions The steric structure of 3-halo-1-thia-3-phosphethanes with a tetracoordinated phosphorus atom was investigated by the methods of dipole moments and Kerr constants, enlisting data on quantum chemical calculations of the energies of the conformations.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2240–2244, October, 1973.The authors would like to thank I. M. Shermergorn for providing the samples for the investigations.  相似文献   

20.
The fundamental molecular aspects of trialkyltin compounds of the type R3SnY have been investigated in view of their applicability as ion-selective components in solvent polymeric membranes. The interaction between these compounds and anions has been studied using 119Sn- and 13C-NMR. Neutral tetracoordinated trialkyltin compounds form a negatively charged pentacoordinated complex upon interaction with Cl-ions in homogeneous organic phases as well as in membranes in contact with aqueous solutions. Although in a homogeneous phase, the electronegative substituent Y determines the complex-formation constant, it has no influence on the potentiometric anion selectivity in liquid membranes containing trialkyltin carriers R3SnY with different Y. The observed selectivity pattern is not given by the magnitude of the stability constants in a homogeneous phase but is dictated by the prevailing association-dissociation process leading to tetracoordinated compounds which change in constitution due to varying sample composition, The results obtained from equilibrium studies of tetravalent mono tin compounds with anions in both homogeneous phase and in two-phase systems confirm the earlier hypothesis that trialkyltin compounds incorporated in solvent polymeric membranes act as electrically neutral carriers for anions.  相似文献   

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