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排序方式: 共有1052条查询结果,搜索用时 15 毫秒
1.
N. F. Kirillov V. V. Shchepin V. S. Melekhin 《Russian Journal of Organic Chemistry》2007,43(11):1628-1631
Methyl 1-(2-bromo-2-methyl-1-oxopropyl)-, 1-(1-bromocyclopentylcarbonyl)-, and 1-(1-bromocyclohexylcarbonyl) cyclobutanecarboxylates reacted with zinc and aromatic aldehydes to give, respectively, 7-aryl-2,2-dimethyl-6-oxaspiro[3.5]nonane-5,9-diones, 11-aryl-12-oxadispiro[3.1.4.3]tridecane-5,13-diones, and 12-aryl-13-oxadispiro[3.1.5.3]tetradecane-5,14-diones. 相似文献
2.
A generalization of the Heisenberg XXZ model to the case of arbitrary spin with anisotropy of light-plane type is investigated. The base state of the system, the spectrum of excitations over it, and their scattering matrix are found. The magnetic susceptibility of the model for small magnetic fields and the low-temperature heat capacity are computed.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 145, pp. 109–133, 1985. 相似文献
3.
V. V. Shchepin N. F. Kirillov V. S. Melekhin 《Russian Journal of Organic Chemistry》2006,42(10):1486-1489
Reformatsky reagents obtained from methyl 1-bromocyclohexane-and 1-bromocyclopentane-1-carboxylates reacted with aromatic aldehyde phenyl-and benzoylhydrazones to give 3-aryl-2-phenylamino-2-azaspiro[3.5]nonan-, 3-aryl-2-phenylamino-2-azaspiro[3.4]octan-, 3-aryl-2-benzoylamino-2-azaspiro[3.5]-nonan-, and 3-aryl-2-benzoylamino-2-azaspiro[3.4]octan-1-ones, respectively. The reaction of furan-2-carbaldehyde phenylhydrazone with methyl 1-bromocyclohexane-1-carboxylate and zinc led to the formation of 4-(2-furyl)-2-phenyl-2,3-diazaspiro[4.5]decan-1-one. 相似文献
4.
Shchepin V. V. Kirillov N. F. Nedugov A. N. 《Russian Journal of General Chemistry》2003,73(8):1264-1266
Methyl esters of 1-(-bromoisobutyryl)cyclohexanecarboxylic or 3-(1-bromocyclohexyl)-2,2-dimethyl-3-oxopropanoic acids react with zinc and arylglyoxals to form 3-aroyl-4,4-dimethyl-2-oxaspiro[5.5]undecane-1,5-diones or 1-aroyl-4,4-dimethyl-2-oxaspiro[5.5]undecane-3,5-diones, respectively. The former products react with phenylhydrazine, yielding 3-[aryl(2-phenylhydrazono)methyl]-4,4-dimethyl-2-oxaspiro[5.5]undecane-1,5-diones. 相似文献
5.
N. F. Kirillov A. G. Gavrilov P. A. Slepukhin M. I. Vakhrin A. N. Vasyanin S. N. Shurov 《Russian Journal of Organic Chemistry》2012,48(6):767-771
Reformatsky reaction of methyl 1-bromocyclobutane-, 1-bromocyclopentane-, 1-bromocyclohexane-, and 1-bromocycloheptanecarboxylates with 2,5-bis(arylmethylidene)cyclopentanones gave the corresponding 4??-aryl-7??-arylmethylidene-4??,5??,6??,7??-tetrahydro-2??H-spiro[cycloalkane-1,3-cyclopenta[b]pyran]-2??-ones. 相似文献
6.
Sergey P. Gromov Svetlana N. Dmitrieva Artem I. Vedernikov Nikolay A. Kurchavov Lyudmila G. Kuz'mina Yuri A. Strelenko Michael V. Alfimov Judith A. K. Howard 《Journal of Physical Organic Chemistry》2009,22(9):823-833
An improved method for the synthesis of formyl derivatives of N‐methylbenzoazacrown ethers is proposed. They are prepared in up to 68% yields over fewer steps and with a much shorter time required for the last step. The stability constants of complexes formed by N‐methylbenzoazacrown ethers and their structural analogs with alkali metal, alkaline‐earth metal and ammonium cations were determined by 1H NMR titration in CD3CN. High stability of complexes of N‐methyl derivatives of benzoazacrown ethers is demonstrated, comparable with or even exceeding the stability of benzocrown‐ether complexes and markedly exceeding the stability of complexes of phenylazacrown ethers with the same macrocycle size. The structures of azacrown ethers and their complexes with Ba(ClO4)2 were studied by X‐ray diffraction. A high degree of pre‐organization of N‐methylbenzoazacrown ethers toward the formation of complexes with metal and ammonium cations was noted, which is due to the clear‐cut pyramidal geometry of the nitrogen atom and the orientation of the lone electron pairs (LEPs) of most heteroatoms towards the centre of the macroheterocycle. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
7.
The results of ultrasonic action to the substances have been presented. It is examined, the correlation between the electrical
parameters of ultrasonic equipment and acoustic performances of the ultrasonic field in treating the medium, the efficiency
of ultrasonic technological facility, and the peculiarities of oscillations introduced into the load under cavitation development.
The correlation between the acoustic powers of oscillations securing the needed level of cavitation and desired technological
effect, and the electrical parameters of the ultrasonic facility, first of all, the power, is established. The peculiarities
of cavitation development in liquids with different physical-chemical properties (including the molten low-melting metals)
have been studied, and the acoustic power of oscillations introduced into the load under input variation of electric power
to the generator has been also estimated. 相似文献
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