共查询到20条相似文献,搜索用时 46 毫秒
1.
A series of KF/Al2O3 catalyzed Michael-addition reactions between malononitrile and α,β-unsaturated cycloketones in DMF solution were studied. At room temperature, 2-cyano-3-aryl-3-(1,2,3,4-tetrahydronaphthalen-1-one-2-yl) propionitrile derivatives were synthesized by the reaction between 2-arylmethylidene-1,2,3,4-tetra-hydronaphthalen-1-one and malononitrile. However, if the temperature was increased to 80℃, 2-amino-3-cyano-4-aryl-4H-benzo[h]chromene derivatives were obtained in high yields. When the α,β-unsaturated ketones were replaced by 2,6-biarylmethylidenecyclohexanone or 2,5-biarylmethylidenecyclopentanone, another series of 2-amino-3-cyano-4H-pyran derivatives was isolated successfully. The structures of the products were confirmed by X-ray diffraction analysis. 相似文献
2.
DanBiTIAN JunZHU JieFangZHU YuanXiangSHI JinTangWANG 《中国化学快报》2004,15(8):883-884
The β-aminocarboxylic acid derivatives were synthesized by Michael addition reaction ofalkyl amine and α,β-unsaturated carbonyl compounds in the presence of potassium fluoride onalumina. 相似文献
3.
α,β-Unsaturated nitriles were synthesized from the iodine catalyzed reaction of chloro-acetonitrile with aldehydes promoted by tri-n-butylarsine and magnesium. 相似文献
4.
α,β-Unsaturated nitriles were synthesized by the reaction of haloacetonitriles with carbonyl compounds mediated by tri-n-butylstibine in excellent yields. 相似文献
5.
I. Petneházy Zs. M. Jászay Gy. Keglevich L. Toke 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4)
Abstract Reaction of trialkyl phosphites 1 with α,β-unsaturated oxo-compounds 2 gives oxaphospholenes 3 or/and two types of Arbuzov products, γ-keto-phosphonates 4 and alkyl-enol-ethers 5. 相似文献
6.
D. V. Moiseev B. R. James A. V. Gushchin 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):242-254
Abstract Interaction of 3,4-(MeO)2-benzylideneacetone with [HO(CH2)3]3P (THPP) was studied in CD3OD by NMR to compare reactivity of a phenylpropanoid α,β-unsaturated ketone with a corresponding α,β-unsaturated aldehyde. In the presence of HCl, both the ketone and a related cinnamaldehyde first establish an equilibrium with the product formed by nucleophilic attack of the THPP at the C?O bond, [ArCH?CHCX(OD)PR3]+Cl?(X?H or CH3, Ar?Ph or 3,4-(MeO)2C6H3). The ketone salt then slowly transforms into [R3PCH(Ar)CH(D)C(O)CD3]+Cl?, the phosphonium product of nucleophilic attack of THPP at the C?C bond, whereas the final product from the aldehyde is the (α-ether)phosphonium chloride [ArCH?CHCH(OCD3)PR3]+Cl?. In aqueous media, in the absence of HCl, 4-HO-benzylideneacetone, which is similar to a lignin-type, α,β-unsaturated aldehyde model compound, interacts with THPP to afford a stable phosphonium zwitterion, in contrast to the previously studied aldehyde model, which forms dimeric, bisphosphonium products. 相似文献
7.
Wu B Huang H Yang J Zheng N Fu G 《Angewandte Chemie (International ed. in English)》2012,51(14):3440-3443
More Greasy, More Selective: Amine-capped Pt(3) Co nanocatalysts were synthesized and used for the hydrogenation of cinnamaldehyde (CAL). Capping the catalysts with amines that contain long carbon chains results in an ordered surface "array", in which high selectivity towards C?O hydrogenation can be achieved because the C?C bond in CAL does not interact with the surface. The longer the carbon chains in the amine, the higher the selectivity. 相似文献
8.
A series of 2-aminochromene derivatives including 2-amino-ben-zo[ h ] chromene, 2-amino-benzo [ f ] chromene and 2-amino-pyrano [3,2-h ]quinolin derivatives was synthesized from aryl-aldehyde, malononitrile or ethyl cyanoacetate and 1-naphthol or 2-naphthoi or 8-hydroxyquinoline in refluxing ethyl alcohol cat-alyzed by KF-Al2O3. The structures were confirmed by X-ray analysis. 相似文献
9.
Gelson Perin Katiúcia Mesquita Tainara P. Calheiro Márcio S. Silva Eder J. Lenardão Diego Alves 《合成通讯》2014,44(1):49-58
The title compounds were synthesized by a sequential one-pot reaction of aryl aldehydes, aryl-methyl ketones, and thiols promoted by KF/Al2O3. This methodology affords a large number of β-aryl-β-sulfanyl ketone derivatives from aliphatic and aromatic thiols in good yields and is also applicable for solid substrates.
[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献
10.
11.
MA Ya-Ping XING Zhi-Kui ZHU Jin CUI Xin CUN Lin-Feng DENG Jin-Gen 《有机化学》2003,23(Z1):61-61
Michael addition reactions represent one of the most important carbon-carbon bond forming reactions in modern synthetic organic chemistry. [1 ~3] We achieved catalytic enantioselective Michael addition reactions of malononitrile with chiral vicinal diamine-Ru(Ⅱ) complex in the presence of achiral base. High yields and moderate ee were observed. 相似文献
12.
α,β-unsaturated ester coupled with isocyanates or isothiocyanates to give the corresponding thioamides or amides in good yields by SmI2 in the presence of HMPA and t-BuOH in THF at-78°C within a few min. 相似文献
13.
14.
15.
Dr. Xin-Qi Zhu Dr. Qian Wang Prof. Dr. Jieping Zhu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(1):e202214925
We report herein the first examples of chiral phosphoric acid-catalyzed enantioselective Diels–Alder reactions between 2-trifluoroacetamido-1,3-dienes 1 and α,β-unsaturated carbonyl compounds 2 . Polysubstituted 1-acetamido cyclohexenes 3 were formed in high yields with excellent diastereo- and enantioselectivities. The reaction proceeds through a stepwise process as shown by deuterium labelling experiments. A catalytic enantioselective three-component reaction of 1 , 2 and ortho-hydroxybenzhydryl alcohols 4 was subsequently developed furnishing the densely functionalized hexahydroxanthenes 5 in a highly stereoselective manner. This multicomponent reaction generates four chemical bonds with concurrent creation of five contiguous stereocenters. 相似文献
16.
Preparation and properties of magnetic alumina microspheres with a γ-Fe_2O_3/SiO_2 core and Al_2O_3 shell 下载免费PDF全文
Magnetic alumina composite microspheres with γ-Fe 2 O 3 core/Al 2 O 3 shell structure were prepared by the oil column method. A dense silica layer was deposited on the surface of γ-Fe 2 O 3 particles (denoted as γ-Fe 2 O 3 /SiO 2 ) with a desired thickness to protect the iron oxide core against acidic or high temperature conditions. γ-Fe 2 O 3 /SiO 2 /Al 2 O 3 particles with about 85 wt% Al 2 O 3 were obtained and showed to be suitable for practical applications as a magnetic catalyst or catalyst support due to their magnetic properties and pore structure. The products were characterized with scanning electron microscope (SEM) and transmission electron microscope (TEM), nitrogen adsorption-desorption, and vibrating sample magnetometer (VSM). The specific surface area and pore volume of the γ-Fe 2 O 3 /SiO 2 /Al 2 O 3 composite microspheres calcined at 500 ? C were 200 m 2 /g and 0.77 cm 3 /g, respectively. 相似文献
17.
Sheverdov V. P. Davydova V. V. Nasakin O. E. Maryasov M. A. Dorovatovskii P. B. Khrustalev V. N. 《Russian Journal of General Chemistry》2019,89(3):385-390
Russian Journal of General Chemistry - The reaction of 1-(2-oxocyclohexyl)ethane-1,1,2,2-tetracarbonitrile with crotonic aldehyde, cinnamic aldehyde, 2-furylacrolein, 3-phenyl-2-propinal,... 相似文献
18.
Copper hydride‐catalyzed conjugate reduction‐intermolecular aldol addition domino reactions were realized using α,β‐unsaturated carboxylates as hydride acceptors and a silane as the reducing reagent. High diastereoselectivities were achieved with 4,5‐bis(diphenylphosphino)‐9,9‐dimethylxanthene as the ligand and tert‐butyl acrylate as the hydride acceptor. 相似文献
19.
Heterobicycles of δ-lactam fused with imidazolidine (4, 7), hexahydropyrimidine (5, 8), or hexahydro-1, 3-diazepine (6, 9) were synthesized by the reaction of heterocyclic ketene aminals 1, 2 or 3 with ester of α,β-unsaturated carboxylic acids. 相似文献
20.
1-Aryl-2-(4-nitrophenylsulfonyl)ethanones (1) reacted with one equiv. of α,β-unsaturated esters at 60°C to afford the tandem addition-rearrangement products (3), while at 75°C 1a reacted with two equiv. of methyl acrylate and gave an unexpected addition-rearrangement-addition-annulation product which is dimethyl 4-hydroxyl-1-(4-nitrophenyl)-4-phenyl-1,3-cyclohexyldicarboxylate (4). A mechanism is suggested. 相似文献