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1.
《广州化学》2015,(4):55-58
以2-甲基-3-硝基苯甲醛为原料,通过还原、氯代和氰代单元反应合成出2-甲基-3-硝基苯乙腈,经过制备单晶并用X-射线衍射表征其为2-甲基-3-硝基苯乙腈晶体结构,化合物属单斜晶系,空间群为P2_1/C,分子式C_9H_8O_2N_2,Mr=176.18,晶胞参数a=17.26(3)?、b=1.7950(14)?、c=15.746(3)?、b=117.10(3)°、V=1736.3(7)?3,晶胞密度(计算值)为1.348 Mg·m~3、Z=8、R=0.073、wR=0.197。二个分子组成一个不对称的单元,分子间的芳香环形成20.15(7)o的二面角。 相似文献
2.
以邻二甲苯为原料,通过硝化、氧化、水解和还原反应得到2-甲基-3-硝基苯甲醇,将其培养得其单晶后用X-射线衍射表征。2-甲基-3-硝基苯甲醇分子式C_8H_9NO_3,晶体属单斜晶系,空间群为P2_1/n,Mr=167.16,晶胞参数:a=13.601(3)?,b=7.8650(16)?,c=15.433(3)?,β=92.73(3)o,V=1 649.0(6)?~3,计算晶胞密度为1.347 mg/m~3,Z=8,R=0.061,ωR=0.189。两个分子通过氢键连接在一起,两个芳香环形成83.29(3)o的二面角。 相似文献
3.
在低转光解情况下,1-萘甲腈(1-NpCN)和2,3-二甲基丁烯-2(DMB)在环已烷或苯中的光环加成反应主要得到环丁烷3,但2-NpCN主要得到氨杂环丁烯6和少量的环丁烷5,三氟醋酸(TFA)量增加抑制1-NpCN和DMB的光环加成反应,表明TFA与基态及单激发态1-NpCN生成非光反应的复合物,它也淬灭^*(1-NpCN-DMB)激基复合物.在低浓度范围(0.1M以下)TFA加速2-NpCN和DMB光环加成反应,但在高浓度范围(大于0.1M)时又抑制反应.这些结果被解析如下:^*(2-NpCN-DMB)激基复合物和TFA反应增加5和6的得率,反之,是由于生成非光反应的基态复合物及淬灭单激发态2-NpCN.在非极性溶剂中二种单激发态萘甲腈生成TFA激基复合物的萤光与母体^*NpCN萤光区域几乎相同. 相似文献
4.
以对氨基苯腈为起始原料,经胺化反应制得N-(4-氰基苯基)甘氨酸(4);4与N-[3-氨基-4-(甲基氨基)苯甲酰基]-N-2-吡啶-β-丙氨酸乙酯(5)经酰胺化后经闭环反应,合成了达比加群酯的关键中间体——3-【【【2-{[(4-氰基苯基)氨基]甲基}-1-甲基-1H-苯并咪唑-5-基】羰基】(吡啶-2-基)氨基】丙酸乙酯,总收率79.6%,其结构经~1H NMR和ESI-MS确证。 相似文献
5.
由2-甲氧基-6-硝基苯胺制得的3-甲氧基-4-氯-5-硝基苯甲腈(Ⅰ)是作者等合成美登素芳香部分的关键中间体。后来孙菡丽等从原料香兰素(Ⅱ)开始也制得了(Ⅰ)。最近,我们又研究出由香兰素制备 相似文献
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以3-硝基-2-氨基苯甲酸甲酯为原料,经三氟乙酰化、N-烷基化和脱保护反应制得坎地沙坦中间体2-{[(2'-氰基联苯基-4-基)甲基]氨基}-3-硝基苯甲酸甲酯,其结构经~1H NMR,~(13)C NMR和MS(ESI)确证。 相似文献
10.
三甲基硅化腈是一种常用的有机合成试剂. 对近年来三甲基硅化腈在有机合成中的应用进行了简要的总结和概述, 重点介绍了三甲基硅化腈作为强的亲核试剂广泛用于环氮和环氧化合物的开环反应、亚胺和醛酮类化合物的加成、胺与醛或酮参与的多组分反应、偶联反应以及对炔和具有较高活性的碳碳双键的氰化加成等反应. 相似文献
11.
K. I. Matveev E. G. Zhizhina V. F. Odyakov V. N. Parmon 《Russian Chemical Bulletin》1994,43(7):1142-1145
2-Methyl-1-naphthol is oxidized into 2-methyl-1,4-naphthoquinone (menadione) by air in the presence of vanadomolybdophosphoric heteropolyacids and their salts. The reaction proceeds in a biphasic system, and the yield of menadione is up to 85 %. The influence of the composition of the heteropolyacids on the rate and the selectivity of the reaction was studied, and the reaction mechanism was proposed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1208–1211, July, 1994. 相似文献
12.
Syntheses of 2,5-bis(4-methyl-2-thienyl)thiophene 3 and 2,5-bis(4-methyl-2-thienyl)pyrrole 4 are described. The key step involves Stetter reaction between 4-methyl-2-thiophenecarboxaldehyde and divinyl sulfone. Cyclizaton of the resulting 1,4-bis-(4-methyl-2-thienyl)-1,4-butanedione 2 with Lawesson's reagent gives 2,5-bis(4-methyl-2-thienyl)thiophene 3, whereas condensation with ammonium acetate provides the 2,5-bis(4-methyl-2-thienyl)pyrrole 4. 相似文献
13.
A. A. Korlyukov M. G. Voronkov É. A. Zelbst E. A. Grebneva O. M. Trofimova M. Yu. Antipin 《Journal of Structural Chemistry》2008,49(4):732-736
The molecular structure of 1-methyl-1-fluoroquasisilatrane (2-methyl-2-fluoro-1,3-dioxa-6-aza-2-silacyclooctane) MeFSi(OCH2CH2)2NH (I) is determined by single crystal X-ray diffraction at 100 K. The coordination polyhedron of the silicon atom in this molecule is a slightly distorted trigonal bipyramid with an NH group and a strongly electron-withdrawing fluorine atom in the axial positions, and two endocyclic oxygen atoms and a CH3 group in three vertices of the equatorial plane. The axial angle N→SiF is 171°. The length of the transannular donor-acceptor bond N→Si (2.058 Å) is as small as in 1-fluorosilatrane. The axial bond F-Si (1.660 Å) is longer than that in 1-fluorosilatrane and tetrahedral silicon compounds. 相似文献
14.
V. V. Nikitenko A. I. Martynenko S. A. Ostrovsky V. V. Rusak V. V. Kryuchkov D. A. Topchiev 《Russian Chemical Bulletin》1993,42(2):378-380
3-Methyl-l-vinylpyrazole (M3VP) and 5-methyl-1-vinylpyrazole (M5VP) were isolated as individual substances by vacuum rectification of their mixture (M3VP: M5VP 60 40). For each of them the kinetics of free-radical polymerization in MeOH were measured at low conversions. In both cases the rate of polymerization is proportional to 0.5 order with respect to the initiator (AIBN) concentration. On the other hand, a first order of reaction with respect to monomer concentration is observed only when the latter is relatively low (3M). At higher initial concentrations of monomers the order of reaction becomes less than unity. The overall rate of polymerization for M5VP was higher than for M3VP, whereas the initiation rate remained constant in the whole range of monomer concentrations and did not depend on the exact structure of the monomer. The difference in the rates of polymerization observed for M3VP and M5VP is probably connected with the difference in the key parameterk
p/k
t
1/2
for each of the two isomers. It is concluded that the correct kinetic information about homo- and co-polymerization of M3VP and M5VP cannot be obtained without their adequate separation.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 413–415, February, 1993. 相似文献
15.
A. Kh. Mamleev R. V. Galeev L. N. Gunderova M. G. Faizullin A. A. Shapkin 《Journal of Structural Chemistry》2006,47(2):367-370
Microwave spectrum of 2-methyl-1,3-dioxane has been investigated in the frequency range 8–40 GHz. Rotational a-type and c-type
transitions with J≤40 have been identified. Rotational constants A = 4658.122(2) MHz, B = 2503.221(1) MHz, C = 1783.950(1) MHz and centrifugal distortion constants for the ground vibrational state have been found. Dipole moment components
μa = 1.43 ± 0.01 D, μc = 1.15±0.01 D and overall dipole moment μ = 1.84±0.02 D have been determined. The data obtained are in accord with the chair conformation of the molecule having equatorial arrangement of the methyl group.
Original Russian Text Copyright ? 2006 by A. Kh. Mamleev, R. V. Galeev, L. N. Gunderova, M. G. Faizullin, and A. A. Shapkin
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Translated from Zhurnal Strukturnoi Khimii, Vol. 47, No.2, pp. 373–375, March–April, 2006. 相似文献
16.
Synthesis of 6α-methyl-16α,17α-cyclohexano-19-norprogesterone from a 19-methyl-6-desmethyl precursor
After prolonged refluxing of 19-tosyloxy-16α,17α-cyclohexanopregn-5-en-3β-ol-20-one (3) with NaI in 2-propanol, the initially formed 19-iodo derivative (4) undergoes supraface migration of the CH2I group from the C(10) atom to the C(6) atom, probably through involvement of a homoallyl cation. The resulting 6β-iodomethyl-16α,17α-cyclohexano-19-norpregn-5(10)-en-3β-ol
(5) was transformed in three steps into 6α-methyl-16α,17α-cyclohexano-19-norprogesterone (6α-methyl-19-nor-D′
6-pentarane,8). The transformation of compound5 into the target product8 also gave a side product, a pentarane with aromatic ringA (10), which was isolated and characterized by spectroscopic methods.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1688–1691, September, 1997. 相似文献
17.
A series of 1-methyl-1H-benzimidazole-based compounds, 2-(4?-alkoxy-1,1?-biphenyl-4-yl)-1-methyl- 1H-1,3-benzimidazole derivatives (nPPMx-M) with terminal hydrogen, methyl and nitro moieties (coded as nPPMH-M, nPPMM-M and nPPMN-M, respectively), were prepared and their structures were characterised. The compounds display enantiotropic smectic mesophases for hydrogen and methyl terminated compounds (nPPMH-M and nPPMM-M), and enantiotropic nematic mesophases for nitro terminated compounds (nPPMN-M) with short alkoxy chain below than 10 carbon atoms, where the mesophase ranges are 24–72°C and 74–104°C on heating and cooling processes for nPPMH-M, 90–119°C and 110–135°C for nPPMM-M, and 102–129°C and 113–207°C for nPPMN-M, respectively. It is noted that the compounds nPPMx-M exhibit much lower melting points and much wider mesophase range both in heating and cooling than non-1-methyl substituted analogs, which are ascribed to the disruption of hydrogen bonding among the molecules caused by methyl substitution at 1-position of benzimidazole. Meanwhile, among the compounds nPPMx-M, much wider mesophase ranges are obtained for nPPMM-M and nPPMN-M, indicating a much high mesophase stability for the compounds bearing terminal moiety (CH3 and NO2). 相似文献
18.
Monoterpene derivatives with a cyclopropane moiety in the molecule were prepared by reactions of 3-methyl-3-cyanocyclopropene
with several monoterpenes and terpenoids (β-myrcene, neoalloocimene, alloocimene, β-pinene, carvone). They were formed using
the Diels-Alder reaction, Alder-ene synthesis, conjugated Alder-ene addition, and Diels-Alder cyclization.
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Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 350–353, July–August, 2006. 相似文献
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20.
Grzegorz Lewandowski 《Reaction Kinetics and Catalysis Letters》2002,77(2):325-334
The reaction rate at the initial period during the epoxidation of 2-methyl-2-pentene with tert-butyl hydroperoxide in the presence of Mo(CO)6 as catalyst varies linearly in the range of lower concentrations of olefin, hydroperoxide and catalyst. The reaction is losing the first order character in the region of higher concentrations due to the inhibition with the reaction products. This finds the confirmations in a discrepancy between the concentration and the instantaneous (temporal) reaction order. 相似文献