排序方式: 共有23条查询结果,搜索用时 15 毫秒
1.
Dmitry A. Gruzdev Galina L. Levit Victor P. Krasnov Evgeny N. Chulakov Liliya Sh. Sadretdinova Aleksandr N. Grishakov Marina A. Ezhikova Mikhail I. Kodess Valery N. Charushin 《Tetrahedron: Asymmetry》2010,21(8):936-942
A comparative study of the kinetic resolution of racemic 2-methyl-1,2,3,4-tetrahydroquinoline and 2,3-dihydro-3-methyl-4H-1,4-benzoxazine using N-phthaloyl-(S)-amino acyl chlorides as chiral acylating agents is described. Temperature and solvent effects on the stereochemical features have been examined. It has been found that N-phthaloyl-(S)-phenylalanyl and N-phthaloyl-(S)-2-phenylglycyl chlorides bearing aromatic substituents close to the stereogenic centre are more stereoselective acylating agents than N-phthaloyl-(S)-alanyl chloride. For the preparative kinetic resolution of racemic amines N-phthaloyl-(S)-phenylalanyl chloride proved to be the most appropriate chiral acylating agent. 相似文献
2.
V. P. Krasnov A. M. Demin G. L. Levit A. N. Grishakov L. Sh. Sadretdinova V. A. Ol’shevskaya I. V. Glukhov V. N. Kalinin V. N. Charushin 《Russian Chemical Bulletin》2008,57(12):2535-2539
A determination of enantiomeric purity of 1-substituted (Me, Ph, and Pri) 3-amino-1,2dicarba-closo-dodecaboranes by HPLC on chiral Chiralcel OD-H and Chiralpac AD stationary phases involving preliminary phthaloylation of
3-aminocarboranes has been suggested as a general method. 相似文献
3.
O. V. Fedorova M. S. Valova Yu. A. Titova I. G. Ovchinnikova A. N. Grishakov M. A. Uimin A. A. Mysik A. E. Ermakov G. L. Rusinov V. N. Charushin 《Kinetics and Catalysis》2011,52(2):226-233
The effect of nanosized metal oxides on the regio- and stereoselectivity of the multicomponent Biginelli reaction and the
reaction mechanism under conditions of heterogeneous catalysis were studied. It was found that the considerable activation
of reagents occurred on the surface of metal nanooxides. The Biginelli reaction occurred by two mechanisms: a carbocationic
mechanism took place along with the generally accepted mechanism (through the N-acyliminium ion). Nanosized metal oxides in the presence of chiral inductors increased the regio- and stereoselectivity of
the Biginelli reaction. 相似文献
4.
V. A. Bakulev V. S. Mokrushin A. N. Grishakov Z. V. Pushkareva 《Chemistry of Heterocyclic Compounds》1982,18(7):731-736
The IR, UV, and PMR spectra of 5(4)-mercaptoimidazole-4(5)-carboxamide, 5(4)-hydroxyimldazole-4(5)-thiocarboxyamide, 5(4)-mercaptoimidazole-4(5)-thiocarboxamide, and the corresponding methyl derivatives were studied. It is shown that the mercaptoimidazoles obtained exist in the form of zwitterions in solution. The methylation of the mercapto- and hydroxyimidazoles with various methylating agents in solvents was investigated, and the reaction of the thioamides with hydrazine was carried out.See [1] for Communication 10.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 957–962, July, 1982. 相似文献
5.
Atomic metallic hydrogen, which has a lattice with the FDDD unit cell symmetry, has been shown to be a stable phase at a hydrostatic pressure of 350–500 GPa. The found structure has a phonon spectrum which is stable with respect to decay. The structural, electronic, phonon, etc., characteristics of normal metallic phases of hydrogen at a pressure of 350–500 GPa have been ab initio calculated. 相似文献
6.
7.
A. Yu. Vigorov I. A. Nizova K. E. Shalunova A. N. Grishakov L. Sh. Sadretdinova I. N. Ganebnykh M. A. Ezhikova M. I. Kodess V. P. Krasnov 《Russian Chemical Bulletin》2011,60(5):873-881
Nucleophilic substitution of the halogen atom in dimethyl (S)-4-bromoglutamate followed by removal of the protecting groups and closure of a lactam ring afforded (2S,4S)-4-(indolin-1-yl)-5-oxoproline. The indoline fragment was oxidized into the indole fragment to give (2S,4S)-4-(indol-1-yl)-5-oxoproline; reduction of the carbonyl groups with BH3 yielded (2S,4S)-4-(indol-1-yl)prolines and (2S,4S)-2-hydroxymethyl-4-(indol-1-yl)pyrrolidines. Reduction of (2S,4S)-4-arylamino-5-oxoprolines with BH3 to the corresponding (2S,4S)-4-arylaminoprolines and (2S,4S)-4-arylamino-2-hydroxymethylpyrrolidines was studied. 相似文献
8.
JETP Letters - A new solid atomic phase of nitrogen, which is dynamically stable at pressures above 20 GPa, has been predicted within the density functional theory. This phase has a low symmetry of... 相似文献
9.
M. A. Salem K. S. Grishakov M. A. Gimaldinova 《Bulletin of the Lebedev Physics Institute》2018,45(8):227-229
The formation energy and the Stone—Wales defect structure in fullerene C20 doped with one of functional groups H, Cl, F, or OH are calculated within the density functional theory. It is shown that the functional group type and binding site have a significant effect on the defect formation energy. It is found that the C20F compound is significantly more stable than other considered systems, i.e., C20Cl, C20H, and C20OH. 相似文献
10.
Physics of the Solid State - The quantum chemical simulation of adsorption of atomic hydrogen on pristine and nitrogen-doped graphdienes has been performed. The preferential sites, adsorption on... 相似文献