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1.
2.
Summary The photochemical and aluminium chloride-catalyzed Fries rearrangement of a series of aryl hydrogen succinates3 a–f to the corresponding 4-oxoacids1 a–f are compared. Both approaches are complementary: the photochemical process is more general and becomes the method of choice for the succinoylation of phenols supporting alkoxy or hydroxy substituents, while the classical rearrangement is superior in the presence of alkyl or halogen substituents. These results are applied to the preparation of the 2(3H)-furanones2 a–f.
Photochemische und Aluminiumchlorid-katalysierte Friessche Umlagerung von Bernsteinsäuremonoarylestern. Synthese von 2(3H)-Furanonen
Zusammenfassung Die photochemische und AlCl3-katalysierte Friessche Umlagerung einer Reihe von Bernsteinsäuremonoarylestern3 a–f zu den entsprechenden 4-Oxosäuren1 a–f werden verglichen. Beide Methoden ergänzen einander: Der photochemische Prozeß ist breiter anwendbar und wird bei Phenolen mit Alkoxy- oder Hydroxy-Substituenten bevorzugt, während die klassische Umlagerung in Gegenwart von Alkyl- oder Halogen-Substituenten vorteilhafter ist. Diese Ergebnisse werden für die Synthese der 2(3H)-Furanone2 a–f angewendet.
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3.
Summary The Claisen rearrangement of 7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one (2 a) gave 7-hydroxy-8-(1-phenyl-2-propenyl)-3-phenyl-(4H)-1-benzopyran-4-one (3 a) and 2,3-dihydro-2,6-diphenyl-3-methyl-(7H)furo[2,3-h]-1-benzopyran-7-one (7 a). 2-Methyl-7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one (2 b) afforded4 b and7 b. 8-Methyl-7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one (12) gave only the alkali soluble product 7-hydroxy-8-methyl-6-(1-phenyl-2-propenyl)-3-phenyl-(4H)-1-benzopyran-4-one (13).3 a,4 b, and13 were further cyclized in acidic medium to9 a,10 b, and14 followed by dehydrogenation.This paper is dedicated to Dr. F. M. Dean, Department of Organic Chemistry, Robert Robinson Laboratories, University of Liverpool, Liverpool, U. K., on his retirement  相似文献   

4.
用Heck反应合成1-羟基-4-(3-吡啶基)丁-2-酮   总被引:1,自引:0,他引:1  
蔡春  吕春绪 《有机化学》2004,24(6):673-674
在Heck反应条件下,以Ph3P为催化剂配体,由3-卤代吡啶和3-丁烯-1,2-二醇进行偶合可以得到1-羟基-4-(3-吡啶基)丁-2-酮,具有原料易得、合成方法简单的优点.  相似文献   

5.
An efficient method for the stereoselective synthesis of 3-(diarylmethylene)-2-oxindoles and 3-(arylmethylene)-2-oxindoles via carbopalladation is described. In this approach, an Ugi-4-component reaction (4-CR) adduct was used as the starting material. A one-pot sequence involving intermolecular carbopalladation C-H activation/C-C bond formation efficiently afforded the oxindole derivatives.  相似文献   

6.
吴小云  尹晓刚  龚维  陈治明  陈卓 《化学通报》2016,79(12):1156-1160
以氰基查尔酮类化合物及丙二腈为原料,醋酸锌为催化剂,经串联反应合成2-氨基-4H-吡喃类衍生物。考察催化剂、溶剂、反应时间及温度、原料摩尔比对产率的影响。最优条件为:氰基查尔酮类化合物与丙二腈物质的量比为1.0:1.0,醋酸锌(10mol%)作催化剂,二氯甲烷作溶剂,反应温度为30℃,产率最高为99.5%。  相似文献   

7.
The Amberlite XAD-7 resin modification was carried out by loading 2-(1-(4-chlorophenyl)-4,5-diphenyl-1H-imidazol-2yl)-4-nitrophenol (CPDPINP). Subsequently, this new sorbent was applied for the enrichment of metal ions such as Cu2+, Ni2+, Co2+ Zn2+ and Pb2+ ions. The effect of various parameters on their sorption and following recoveries was studied in column procedure. The preconcentrated ions were eluted by appropriate eluent and their contents were quantified by FAAS. This method has preconcentration factor of 150 and enrichment factor in the range of 20.8–29.1. At optimum values of all variables, the proposed method has linear calibration graphs in the range of 0.01 up to 0.29 μg mL−1 with detection limit (3SDb/m, n = 15) between 1.6 and 2.6 ng mL−1. This protocol is usable for successful analysis of Cu2+, Ni2+, Co2+ Zn2+ and Pb2+ ions in different matrices with reasonable recoveries (>93%) and acceptable relative standard deviation (<4.7%).  相似文献   

8.
《Tetrahedron letters》2019,60(44):151205
A simple and efficient approach for the synthesis of novel 2-carboxanilido-3-arylquinazolin-4-ones via the one-pot condensation of readily available N1-(2-carboxyphenyl)-N2-(aryl)oxalamides with various aromatic amines is described. Notably, this methodology allows us to synthesize 3-aryl-quinazolin-4-ones using aromatic amines with various substituents, both electron-donating and electron-withdrawing, which ensures structural diversity of the products and an atomic-economic process.  相似文献   

9.
An easy, solvent-free method for the synthesis of 1-(4-chlorophenyl)pyrazolidin-3-one has been achieved by grinding 4-chlorophenyl hydrazine and methyl acrylate in the presence of base in a ball mill. A systematic investigation of the reaction has been made in order to study the various factors affecting the reaction.  相似文献   

10.
Potentially bioactive 3-(anilinoarylmethylene)-2-oxindoles as Hesperadin analogoues have been synthesized via a two-step procedure: (a) an Ugi-4MCR and (b) reaction of the Ugi adduct with aniline in the presence of a palladium catalyst via domino Heck/Buchwald reaction. In all cases, a single isomer with the Z-configuration was obtained in good to high yields.  相似文献   

11.
We have developed an effective organometallic‐based procedure allowing the employment of 2‐methylphenols as easily available starting materials in the synthesis of 3‐alkylbenzofuran‐2(3H)‐ones. The first step of this protocol, an anionic homologous Fries‐rearrangement, afforded 2‐(2‐ tert ‐butyldimethylsilyloxyaryl)acetamides, which were selectively metalated and monoalkylated at the benzylic position. Acidic work‐up of crude products afforded the desired heterocycles in satisfactory overall yields. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

12.
<正>The title compound N-(2-(1-butyl-3-phenylureido)-1H-indol-3-yl)-N-(4-chloro- phenyl)- benzamide (C_(32)H_(29)ClN_4O_2, M_r = 537.04) was synthesized by a sequential Ugi four com- ponent condensation (4CC)/aza-Wittig/carbodiimide-mediated cyclization, and the structure was characterized by NMR, IR, MS, elemental analysis and X-ray single-crystal diffraction analysis. The crystal belongs to orthorhombic, space group P2_12_12_1 with a = 11.3663(9), b = 13.3248(10), c = 18.7887(15), V = 2845.6(4)~3, Z = 4, D_c = 1.254 mg/m3, μ = 0.170 mm~(-1), F(000) = 1128, the final R = 0.0538 and wR = 0.1187. X-ray analysis reveals that the new five-membered ring (C(14)-C(15)-N(2)-C(16)-C(21)) and the benzene ring (C(16)-C(21)) are nearly coplanar.  相似文献   

13.
The title compound 2-(2-chloro-4-nitrophenyl)-4-(4-chlorophenyl)-3a,4- diethoxy- 2,3,3a, 4-tetrahydrochromeno[3,4-d][1,2,3]diazaphosphole 2 (C29H30Cl2N3O7P, Mr = 633.44) was synthesized and its structure was characterized by IR, MS, ^1H NMR, ^13C NMR, ^31p NMR, elemental analysis and single-crystal X-ray diffraction. It crystallizes in triclinic, space group P1^-, a = 9.1549(3), b = 10.7168(4), c = 17.6272(6)A, α = 102.9363(12), β = 90.2713(9), γ = 117.4265(10)°, V= 1484.41(9)A^3, Z= 2,μ(MoKa) = 0.323, F(000) = 658, Z= 2, De= 1.417 g/cm^3, the final R = 0.0687 and wR = 0.2066 for 4943 observed reflections (I 〉 2σ(I)). X-ray analysis reveals that the diazaphospholine ring is almost planar and the two ethoxy groups bonded on the 3a- and 4-positions are in trans configurations. Its antiproliferative activity was also tested in vitro against four human tumor cell lines.  相似文献   

14.
本文应用吸收光谱、激光拉曼光谱及量子化学方法研究了5-Cl-PADAB及其钴络合物在不同酸度溶液中存在的形式及络合生色反应的机理,测定了钴络合物的质子化常数。  相似文献   

15.
通过3-取代-4-氨基-5-巯基-1,2,4-三唑(3a~3m)和2-溴-2-(1H–1,2,4-三唑-1-基)-4′-氯代苯乙酮(2)的缩合反应,合成了13个新型3-取代-6-(4-氯苯基)-7-(1H-1,2,4-三唑-1-基)-1',2',4'-三唑[3,4-b]-1",3",4"-噻二嗪衍生物4a~4m.化合物结构经元素分析,1HNMR,IR和MS进行了表征.抗菌试验表明所合成的化合物对细菌表现出中等程度的抑制活性.  相似文献   

16.
Various 3-(hetero)aryl, 3-alkyl and 3-alkenyl-2(1H)-pyrazinones were prepared by applying the Suzuki and Heck reaction methodology to 3,5-dichloro-2(1H)-pyrazinones. Furthermore, following hydrogenolysis of the 5-chloro substituent and regioselective 5-bromination, this palladium-catalysed cross-coupling approach could be extended to the synthesis of the analogous 5-substituted 2(1H)-pyrazinones.  相似文献   

17.
A synthesis of methyl 2-hydroxy-4-oxo-4-(substituted phenyl)butanoates has been accomplished using Friedel-Crafts acylation of substituted benzenes with 2-acetoxybutanoyl chloride.The key feature of this strategy is that various 4-arylbutanoates can be obtained conveniently,which are important intermediates for the synthesis of biologically active compounds including ACE inhibitors.  相似文献   

18.
Oxidation of (E)-3-(4-chlorophenyl)-2-cyanoprop-2-enethioamide with hydrogen peroxide or the H2O2-KOH system gave 3-(4-chlorophenyl)oxirane-2,2-dicarboxamide. This compound was also obtained by an independent “one pot” synthesis from p-chlorobenzaldehyde and 2-cyanoacetamide through in situ oxidation of their adduct (E)-3-(4-chlorophenyl)-2-cyanoprop-2-eneamide with the H2O2-KOH system. The structure of 3-(4-chlorophenyl)oxirane-2,2-dicarboxamide was confirmed by X-ray diffraction and spectroscopic data. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1417–1419, July, 2007.  相似文献   

19.
Dienolates of various γ-allyloxy substituted methyl β-pyrrolidinyl (E)-2-butenoate undergo a [2,3]-Wittig rearrangement to generate various 5-alkenyl-4-pyrrolidin-1-yl-5H-furan-2-one type compounds.  相似文献   

20.
A novel compound N-(pyridine-2-methyl)-2-(4-chlorophenyl)-3-methylbutanamide, a racemic compound, has been synthesized with 2-(4-chlorophenyl)-3-methylbutyric acid and pyridin- 2-methylanamine as the raw materials, and its crystal structure (C17H19C1N2O, Mr = 302.79) was determined by single-crystal X-ray diffraction analysis. The crystal belongs to monoclinic, space group P21/n with a = 9.624(9), b = 23.14(2), c = 15.626(15)A, β = 106.199(14)°, V = 3342(5) A^3, Z = 8, Dc = 1.204 g/cm^3,μ = 0.23 mm^-1, F(000) = 1280, S = 1.032, R = 0.0681 and wR = 0.1508 for 6513 unique reflections (Rint = 0.0421) with 3375 observed ones. In the crystal structure, there are some intermolecular hydrogen bonds which stabilize the crystal structure. The preliminary bioassay shows that the title compound exhibits good antifungal activity against Botrytis cinerea, Gibberella zeae, Dothiorella gregaria and Colletotrichum gossypii.  相似文献   

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