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I. E. Karpeiskaya L. F. Godunova E. S. Levitina M. R. Lyubeznova E. I. Klabunovskii E. S. Shpiro G. N. Baeva E. D. Lubuzh L. B. Krentsel' A. D. Litmanovich N. A. Plate 《Russian Chemical Bulletin》1992,41(10):1858-1867
Pd complexes have been obtained from linear and cross-linked copolymers ofR,S-, R-, andS-1-(4-vinylphenyl)ethylamine (1) with styrene and divinylbenzene. Reduction of these compounds gave catalysts which were active in the reductive solvolysis of -acetaminocinnamic acid azlactone (2) and hydrogenation of the solvolysis products -acetamidocinnamic acid (ACA), its esters, and its 1-phenylethylamide. The catalysts showed no enantioselective properties in the reductive hydrolysis, but were more active than the catalyst obtained in the absence of the polymer (the monomeric analog). The use of polymeric catalysts has shown that, in reductive aminolysis, the chiral nucleophile plays the dominant part in determining the stereoselectivity of the reaction, rather than the chiral ligand of the catalytic complex. The polymer matrix stabilizes the low-valent state of the palladium in the complex. In the hydrogenation of ACA and its esters, the catalyst on the cross-linked polymer is much more active than its monomeric analog, but showed no enantioselectivity. Hydrogenation of acetamidocinnamic acidR-andS-1-phenylethylamides on a chiral Pd-polymer catalyst occurred with double asymmetric induction.Deceased.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. A. V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 117912 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 2368–2380, October, 1992. 相似文献
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E. S. Levitina E. D. Lubuzh L. F. Godunova E. I. Karpeiskaya E. I. Klabunovskii 《Russian Chemical Bulletin》1989,38(5):1011-1014
1. | It has been shown that when 2-methyl- and 2-phenyl-4-benzylideneoxazolin-5-ones react with a-phenylethylamine in dimethoxyethane the rate of opening of the oxazoline ring is dependent on the nature of the substituents at the para-position of the aromatic ring of the benzylidene group. Electron-donating substituents retard the process and electron-withdrawing substituents accelerate it. |
2. | It has been shown that replacement of Me by Ph on C2 of the oxazolone ring results in an increase in rate of aminolysis. |
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E. I. Klabunovskii D. D. Gogoladze E. S. Levitina E. I. Karpeiskaya L. F. Godunova L. N. Kaigorodova G. O. Chivadze 《Russian Chemical Bulletin》1987,36(7):1475-1478
Conclusions The enantioselective hydrogenation of-nitrocaprolactam (I) is effected on a chiral Pd complex, obtainedin situ in the presence of S--phenylethylamine, to give S--aminocaprolactam (II), hydrolysis of which gives S-lysine. The optical yield varies from 1 to 13% according to the solvent and concentration of chiral ligand. On a Pd complex with S-N-isopropyl--phenylethylamine, enantioselective hydrogenation of (I) gives an excess of the S-enantiomer of (II) (2%). On a Pd complex with S-phenylalaninol, hydrogenation of (I) leads to the R configuration of (II) with EE 7.2%.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1597–1600, July, 1987. 相似文献
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E. S. Levitina L. F. Godunova L. N. Kaigorodova E. I. Karpeiskaya E. I. Klabunovskii D. D. Gogoladze 《Russian Chemical Bulletin》1986,35(4):842-844
Conclusions The stereoselective aminolysis of the azlactone of DL-diacetyllysine by the action of S--phenylethylamine in t-BuOH leads to an excess of the SS-diastereomer of the -phenylethylamine or diaceyllysine. Crystallization of the mixture of diastereomeric amides gave the optically pure S--phenylethylamide of S-diacetyllysine.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 925–927, April, 1986. 相似文献