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51.
Book Review     
Abstract

A Guide to Organophosphorus Chemistry, by Louis D. Quin, an internationally recognized authority, published by John Wiley and Sons (http://www.wiley.com/chemistry) ISBN 0-471-31824-8, $94.95, 394pp.

Aminophosphonic and Aminophosphinic Acids: Chemistry and Biological Activity. Editors: Valery P. Kukhar (Ukrainian Academy of Sciences) and Harry R Hudson (University of North London). Published by John Wiley and Sons Ltd., Chichester, UK, on 31 March, 2000. ISBN 0 471-89149-5, 175.00 Pounds sterling, 634 pages.

Phosphorus Ylides. Chemistry and Application in Organic Synthesis, by Oleg I. Kolodiazhnyi. Published by Wiley-VCH, 1999, ISBN 3-527-29531-3, 220SF, 555 pages.  相似文献   
52.
The high intrinsic stability of 1,3,2-diazaphospholenium cations enhances ionic polarization of covalent P--X bonds in P -halogeno- and P -hydrido-diazaphospholenes. The physical properties of the latter suggest a hydridic nature of the P--H bond, and their reactivities display an "Umpolung" as compared to known reaction patterns of phosphines.  相似文献   
53.
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   
54.
55.
The stable singlet carbenes N,N '-bis(2,2-dimethylpropyl)-benzimidazolin-2-ylidene 1 and 1,3,4,5-tetramethylimidazol-2-ylidene 2 react with phosphaalkynes P L C-- t Bu ( 3a ) or P L C--N i Pr 2 ( 3b ) regioselective to give the aromatic 1,2,4-triphosphole derivatives ( 1 or 2 + 3a M 6a or 6b , respectively) or 1,2,3-triphosphetene ( 1 + 3b M 7 ) or azaphospholene ( 2 + 3b M 9 ) in almost quantitative yields. The mechanisms of the surprising formation of compound 9 under C--H-activation was studied by quantum chemical DFT calculations.  相似文献   
56.
The lone pair-lone pair repulsion plays an important role in the nonbonded P;;;P interaction in naphthalene 1,8-positions. The conformations around P and Se in 8-(PhSe)-1-(Ph 2 P=O)C 10 H 6 are determined by the attractive O;;;Se--C 3c-4e type interaction. The P;;;Se interaction in the 1,8-positions is also discussed.  相似文献   
57.
( Z )-2-Chloro-3,3-diphenyl-1-(2,4,6-tri- t -butylphenyl)-1,3-diphosphapropene was derived from chlorodiphenylphosphine and 1-chloro-2-(2,4,6-tri- t -butylphenyl)-2-phosphaethenyllithium and utilized for complex formations as a ligand of the corresponding carbonyl-tungsten(0) complexes.  相似文献   
58.
Abstract

The treatment of 2-acetylthiophene with phosphorus pentachloride led, besides other products reported in previous studies, to 2-(2-thienyl)-2-chloroethenephosphonic acid in 16% yield. This compound was transformed, in the course of purification attempts, into 2-(2-thienyl)-2-oxoethanephosphonic acid. Full spectroscopic data for both compounds are provided.  相似文献   
59.
Abstract

Several infrared and Raman studies have been performed on compounds containing the disulfide group in the region of C-S and S-S stretching modes (1–4) in order to get a better insight of the correlations between molecular conformation and peculiar geometry parameters of the dihedral angle CS-SC.  相似文献   
60.
The synthesis and characterization of several new phosphorus-containing partially lower rim substituted derivatives of 5,11,17,23-tetra(t-butyl) calix(4)arene (I) and 5,11,17,23-tetra(t-octyl)calix(4)arene (II), namely 5,11,17,23-tetra(t-butyl)-25,27-dihydroxy-26,28-bis(diphenylphosphinoyl-oxy) calix(4)arene (IV); 5,11,17,23-tetra(t-butyl)-25-hydroxy-26,27,28-tris(tetramethyldiamido-phosphinoyl-oxy) calix(4)arene (Vb); 5,11,17,23-tetra(t-butyl)-25,27-dihydroxy-26,28-bis(dimethyl-phosphinoyl-methoxy) calix(4)arene (VI); 5,11,17,23-tetra (t-octyl)-25,27-dihydroxy-26,28-bis(dimethyl-phosphinoyl-methoxy) calix(4)arene (VII) are reported. The structure of the synthesized calix(4)arene derivatives are identified and confirmed by elemental analysis, IR, 1H, 13C, 31P{1H} NMR spectroscopy and mass spectrometry as and X-ray crystallographic analysis of 5,11,17,23-tetra(t-butyl)-25,27-dihydroxy-26,28-bis(dimethyl-phosphinoyl-methoxy) calix(4)arene VI. According to the NMR spectra, all calix(4)arenes are in cone conformation.  相似文献   
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