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21.
22.
A. S. Ionkin S. N. Ignat'eva V. M. Nekhoroshkov Yu. Ya. Efremov B. A. Arbuzov 《Russian Chemical Bulletin》1990,39(9):1938-1939
P-Phenyl-C,C-bis(trimethylsilylthio)methylenephosphine is hydroborated with dicyclohexylborane, with the hydroboration product undergoing spontaneous elimination with the formation of trimethylsilylthio(dicyclohexyl)borane and P-phenyl-C-trimethylsilylthiomethylenephosphine.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2127–2129, September, 1990. 相似文献
23.
The nature of the dialkylamino group has a significant effect on the reactivity of C-(N,N-di-alkylamino)phosphaalkenes upon their reaction with sulfur.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1169–1172, May, 1990. 相似文献
24.
PhSCl adds regiospecifically to the P=C double bond in C-(N,N-dimethylamino)-methylene-P-phenylphosphine to give PhP(SPh)2 and Cl2CHNMe2.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 948–949, April, 1991. 相似文献
25.
Prior bounds expressing stability in the right-hand side are constructed for difference schemes approximating the heat equation
with nonlocal boundary conditions. The constraints on the grid increment guaranteeing stability in the right-hand side are
identical with the previously established criteria for stability in initial values.
__________
Translated from Prikladnaya Matematika i Informatika, No. 23, pp. 134–139, 2006. 相似文献
26.
A. S. Ionkin S. N. Ignat'eva O. A. Erastov B. A. Arbuzov Yu. Ya. Efremov V. M. Nekhoroshkov 《Russian Chemical Bulletin》1989,38(7):1536-1537
Conclusions Unstable methylenephenylphosphine may be trapped by dialkylborane. The hydroborylation reaction proceeds with the formation of a product with a P-H bond.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1674–1676, July, 1989. 相似文献
27.
B. A. Arbuzov O. A. Erastov A. S. Ionkin S. N. Ignat'eva 《Russian Chemical Bulletin》1987,36(2):377-381
Conclusions Treatment of phenylbis(hydroxymethyl)phosphine sulfide with acetals and ketals gives the corresponding 2-substituted and 2,2-disubstituted 5-phenyl-5-thio-1,3,5-dioxaphosphorinanes in which the P-Phenyl substituent occupies an axial position.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 418–422, February, 1987. 相似文献
28.
Intramolecular charge separation from the second singlet excited state of directly linked Zn-porphyrin-imide dyads and following charge recombination into the first singlet excited state has been investigated in the framework of a model involving three electronic states (the first and the second singlet excited and charge separated states) as well as their vibrational sublevels. Kinetics of the transitions between these states are described in terms of the stochastic point-transition approach. The influence of the model parameters (free energy change of charge separation, magnitude of the reorganization energies of the medium and the high frequency intramolecular vibrations, the rate of relaxation of the medium and the intramolecular high frequency vibrational mode) on the kinetics of population of both the charge separated and the first singlet excited states has been explored. Simulations of the kinetics of the charge separated state population have allowed reproducing the distinctive features of the kinetics observed in the experiment [Wallin, S.; Monnereau, C.; Blart, E.; Gankou, J.-R.; Odobel, F.; Hammarstr?m, L. J. Phys. Chem. A 2010, 114, 1709]: (i) two maxima on short time scale (hundreds of femtoseconds) and long time scale (tens of picoseconds), (ii) the magnitudes of both maxima, and (iii) the depth of the notch between the maxima. 相似文献
29.
1,2‐Bis[bis(trimethylsilyl)methylchlorophosphino]ethane was prepared by the reaction of 1,2‐bis(dichlorophosphino)ethane and the Grignard reagent of bis(trimethylsilyl)chloromethane. It adds DBN (1,5‐diazabicyclo[4.3.0]non‐5‐ene) in a 1:2 ratio. Subsequent treatment with t‐BuLi converts the adduct to a condensation product, which in its enamine form reacts with MgCl2 (still present from the preparation of 1 ) to give the cyclic magnesium diamide 2 . By additional coordination of the two phosphine sites of the condensation product, 2 attains a tricyclic structure. An unchanged DBN molecule completes the pentacoordination of the magnesium atom. The structure of product 2 has been determined by single crystal X‐ray diffraction. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:197–199, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10122 相似文献
30.
The potential energy hypersurface of the conversion of aminophosphaethyne ( 1 ) to 1-aza-3-phosphaallene ( 2 ) has been studied with the MNDO method. The interconversion includes five intermediate species. The structure and energy of 1 and its isomers produced by a hydrogen shift have been calculated also with ab initio molecular orbital theory by a split valence basis set including a polarization function at the P atom. The results reveal that all the isomers are equilibrium structures. The ab initio calculation predicts the carbenaazaphosphirane 3 to be the intermediate lowest in energy. It is suggested that a carbene ( 3 ), phosphinidene ( 4 ) or azaphosphirene ( 5 ) are responsible for the 1-aza-2,4-diphosphole formation. 相似文献