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1.
Abstract

It has been established that in the phosphoryl-hydroxyylide systems (I-VIII) the increasing acidity of the carbon atom depending on substituent Y (which is characterized by [sgrave]? CH value) shifts the equilibrium to the hydroxyylide form (B).  相似文献   
2.
Abstract

Direction of alkylation of phosphoranes (I) depends on the nature of the substituent Y and the alkylating agent. Unsubstituted phosphorane reacts with CH3J yielding only the product of C-methylation (II), whereas the reaction with Me2SO4 proceeds at both ends of the OPC-triad, preferably yielding the O-alkylation product (IIIa, 80%).  相似文献   
3.
2-Oxo-1,2-azaphospholanes and 1,2-azaphospholanium salts containing an amino acid fragment were synthesized by intramolecular P-alkylation of N-3-chloropropyl-substituted tricoordinate phosphorus amides. Hydrolysis of 2-oxo-1,2-azaphospholanes at the P-N bond gives rise to γ-aminopropylphosphonic acid derivatives. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2557–2562, November, 2005.  相似文献   
4.
A reaction of N-allyl-substituted aminomethylene-1,1-bisphosphonates with aromatic nitrile N-oxides was used to obtain new aminomethylenebisphosphonates with one or two 3-arylisoxazoline rings at the nitrogen atom. NMR spectroscopy studies showed that the bisphosphonates with two isoxazoline fragments in the molecule exist in solution as a mixture of two diastereomers.  相似文献   
5.
6.
The crystalline complex [Ag(L 1)NO3]2 (A) was isolated by the interaction of (N,N-diethylcaibamoylmethyl)diphenylphosphine sulfide Ph2P(S)CH2C(O)NEt2 (L 1) with AgNO3 in different solvents at the ratios of metal:ligand = 11 and 12. According to the X-ray data, complexA is a center-symmetric dimer with bridge sulfur atoms. The cations of the metal are in a tetrahedral environment formed by two S atoms and the O atoms of CO and NO3 groups. The interaction ofL 1 with AgNO3 was studied in solution by IR spectroscopy, and the structures of the complexes formed are discussed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 708–713, April, 1994.The authors are grateful to B. V. Lokshin and his coworkers for help in measurement of the Raman spectra and for useful discussion.The present investigation was financially supported by the Russian Foundation for Basic Research (Project 93-03-4351).  相似文献   
7.
Abstract

Two new types of tautomerism are discussed: phosphoryl-hydroxyylide and thiophosphoryl-mercaptoylide tautomerism.  相似文献   
8.
The behavior of the phosphine-phosphine sulfide complexes of silver, [Ph2P(S)(CH2) n PPh2] m ·AgNO3 (n=2 or 4;m=1 or 2), in pyridine was studied. Dissolution of the 1:1 complexes in pyridine leads to destruction of their dimeric structures Ag2[Ph2P(S)(CH2) n PPh2]2(NO3)2 (A) to form the complexes Agpy +−P(Ph2)(CH2) n Ph2P=S and Agpy +−S=PPh2(CH2) n PPh2. The solid complexes isolated from pyridine restore dimeric structure A. According to the data of X-ray diffraction analysis, the 1:2 complex isolated from pyridine has the structure [S=P(Ph2)(CH2)2(Ph2)P−(NO3)Ag(Py)−P(Ph2) (CH2)2(Ph2)P=S]Py. According to the data of IR spectroscopy, dissolution of this complex in chloroform leads to the formation of the dimeric structure Ag2Ph2P(S)(CH2)2PPh2]4(NO3)2. Deceased. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1751–1758, September, 1998.  相似文献   
9.
Results have been generalized for investigations on the synthesis of 1,2-thiaphosphacyclanes by intramolecular P=S alkylation of -haloalkyl substituted compounds of four-coordinated phosphorus with a P=S bond. The method has been extended to nitrogen-containing analogs with a P=N bond. A new general method is proposed for the synthesis of 1,2-thia- and 1,2-azaphosphacyclanes.  相似文献   
10.
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