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1.
Haotian Xing Long Chen Yimin Jia Zhongxing Jiang Zhigang Yang 《Tetrahedron letters》2017,58(23):2199-2202
A simple, effective approach for the Pummerer rearrangement of acyl chlorides with sulfoxides by using a low-cost and more abundant Fe catalyst has been described. The alkylthiomethyl ester products were prepared in good to excellent yields for a range of different substrates including asymmetrical sulfoxides and acyl chlorides with a variety of functional groups under mild reaction conditions. The reaction features short reaction time, simple manipulation, cheap reagents and a broad substrate scope. Single crystal X-ray analysis of a representative methylthiomethyl (MTM) group containing product was also reported. 相似文献
2.
Olivier Dirat Alex Clipson Jason M. Elliott Sasha Garrett A. Brian Jones Michael Reader Duncan Shaw 《Tetrahedron letters》2006,47(11):1729-1731
The regioselective, scaleable synthesis of three 4-(2-alkyl-5-methyl-2H-pyrazol-3-yl)-piperidines is discussed. 相似文献
3.
4-(1-Alkynyl)-3-bromo- and 4-(1-alkynyl)-3-chloro-2(5H)-furanones have been regioselectively synthesized in moderate to good yields by a new version of the Pd/Cu-catalyzed Sonogashira reaction involving treatment of 1-alkynes with 3,4-dibromo- and 3,4-dichloro-2(5H)-furanone, respectively, in the presence of KF as a base. 4-(1-Alkynyl)-3-bromo-2(5H)-furanones have been found to be able to undergo Stille-type and Suzuki-type reactions with aryl(tributyl)tins and arylboronic acids, respectively, to give 4-(1-alkynyl)-3-aryl-2(5H)-furanones in modest to satisfactory yields. Some 4-(1-alkynyl)-substituted 2(5H)-furanones so prepared have been found to exhibit significant cytotoxic activities, especially against human leukemia cell lines. 相似文献
4.
Dominika JakubiecKrzysztof Z. Walczak 《Tetrahedron letters》2011,52(51):6890-6891
The synthesis of 5-heteroaryl-substituted uracil derivatives is presented. The 1,3-dipolar cycloaddition reaction was applied for the construction of a heterocyclic ring. The nitrile oxides were obtained from the appropriate 4-substituted benzaldoximes using N-chlorosuccinimide (NCS) under basic conditions. [2+3] Cycloaddition of nitrile oxides with 5-cyanouracil as a dipolarophile gave the corresponding 5-(3-substituited-1,2,4-oxadiazol-5-yl)uracils in satisfactory yields under mild conditions. 5-Substituted uracils having an additional heterocyclic ring were obtained as a result of the [2+3] cycloaddition of 5-cyanouracil to nitrile oxides generated from thiophene-2-carbaldehyde and 5-formyluracil derivatives. 相似文献
5.
We hereby report the first preparation of the 3,4-dihydrofuro[3,2-d]pyrimidin-2(1H)-one skeleton formed by two controlled Curtius rearrangements of the corresponding acyl azides, prepared from 2-(2-methoxy-2-oxoethyl)furan-3-carboxylate via the hydrazide. Rearrangement of the acyl azides followed by trapping by nucleophiles and intramolecular trapping provided the target compounds. 相似文献
6.
1-Ehtoxycarbonyl-1, 2-dihydroquinoline-2-phosphonates () were treated with n-butyllithium followed by alkyl halides to afford the corresponding 4-alkylated phosphonates () with complete regioselectivity in 67–97% yields. The phosphonates () were converted to 4-alkylquinolines () in ca. 50% yields by treatment with sodium iodide in HMPA or by alkaline hydrolysis in aqueous ethanol. 相似文献
7.
A simple two-step procedure for the preparation of 2-trifluoromethyl-1(substituted aryl)-4(1H)-quinolones utilizing electrophilic trifluoroacetamidoyl chlorides as the starting materials is described. The cyclization of trifluoromethyl enaminone intermediates with potassium carbonate in hot dimethylformamide produce the trifluoromethylated 4(1H)-quinolones in good to excellent yields. 相似文献
8.
A simple four-step synthesis of 4-(2-aminoethyl)-5-hydroxy-1H-pyrazoles 8 (or their 1H-pyrazol-3(2H)-one tautomers 8′) as the pyrazole analogues of histamine was developed. First, enamino lactam 3 was prepared as the key intermediate in two steps from 2-pyrrolidinone (1). Next, acid-catalysed ‘ring switching’ transformations of 3 with monosubstituted hydrazines 4 gave N-[(1-substituted 5-hydroxy-1H-pyrazol-4-yl)ethyl]benzamides 7a-k and N-[2-(2-heteroaryl-3-oxo-2,3-dihydro-1H-pyrazol-4-yl)ethyl]benzamides 7′l-o. Benzamides 7a-k and 7′l-o were finally hydrolysed by heating in 6 M hydrochloric acid to furnish 1-substituted 4-(2-aminoethyl)-5-hydroxy-1H-pyrazoles 8a-k and 4-(2-aminoethyl)-2-heteroaryl-1H-pyrazol-3(2H)-ones 8′l-o in good overall yields. 相似文献
9.
A facile and efficient reduction of aromatic and aliphatic acyl chlorides to their corresponding aldehydes in the presence of Sm(0)/Bu3P has been developed with broad scope. This method prevents over reduction of products, that is, the over-reduction of aldehydes to alcohols. 相似文献
10.
1-(Alkylamino)-2,4-diarylpyrimido[6,1-a]isoquinolin-5-ium chlorides are obtained in good yields via a tandem reaction between isoquinoline, N-alkyl-benzimidoyl chlorides and alkyl isocyanides in anhydrous acetonitrile. 相似文献
11.
A highly-efficient and practical method for the formation of ynones from a variety of acyl chlorides and terminal alkynes catalyzed by a nanosized MCM-41 anchored palladium bipyridyl complex is described herein. Aroyl, heteroaroyl, and alkyl acyl chlorides were easily coupled with terminal alkynes, giving good to high isolated yields in the presence of a very low catalyst loading (0.002-0.1 mol % Pd) in Et3N or diisopropylethylamine at 50 °C. Furthermore, the reaction scale was up to 150 mmol for a single batch reaction, providing the potential for practically synthetic application. After centrifugation, the supported catalyst was able to be recycled and reused several times with only a slight decrease in activity. 相似文献
12.
Shan-Yen Chou Shieh-Shung Tom Chen Ching-Hui Chen Lien-Shange Chang 《Tetrahedron letters》2006,47(43):7579-7582
3-Methoxy-4-aryl-furan-2,5-dicarboxylic acid (8) is selectively converted into its C-5 methylester (6) by treatment with methyl chloroformate followed by decarboxylation in one flask. Acylation of the resulting half ester with a 7-substituted indole was performed under mild conditions to afford 3-aryl-5-(1H-indole-3-carbonyl)-4-methoxy-2-furoic acid (11). The synthetic utility of the resulting furoic acids as a skeleton in the synthesis of potential insulin receptor activators is established. 相似文献
13.
5-Hydroxy uracils or 4-hydroxy[1]benzopyran-2-ones were refluxed with 2-bromobenzyl bromides in acetone in the presence of anhydrous potassium carbonate to afford a number of 5-(2′-bromobenzyloxy) pyrimidine-2,4-dione (80-92%) or 4-(2′-bromobenzyloxy) benzopyran-7-ones (70-82%) respectively. These were then refluxed with tri-n-butyltin chloride and sodium cyanoborohydride in the presence of a catalytic amount of azobisisobutyronitrile (AIBN) for 3-4 h to give 1H,3H,6H [2]benzopyrano[4,3-d]pyrimidine-2,4-diones (75-85%) or 12H-benzopyrano[3,2-c][1]benzopyran-5-ones (70-85%) respectively. 相似文献
14.
AlCl3-mediated tandem Friedel-Crafts reaction of vinylidenecyclopropanes with acyl chlorides produced the corresponding 1-[2-(2,2-diarylvinyl)-1-phenyl-3H-inden-5-yl]ethanone derivatives in moderate to good yields under mild conditions within short reaction time. 相似文献
15.
16.
An efficient and simple method for the synthesis of 2-unsubstituted 1-aryl-4- and 1-aryl-5-acylimidazoles has been developed. It consists in the condensation of α-diketone monooximes with aromatic amines and formaldehyde on the presence of boron trifluoride etherate, leading to the formation of stable boron trifluoride complexes of N-oxides. Further reduction of these complexes led to the corresponding imidazoles. This method permits broad variations of substituents in the aryl part of these compounds. 相似文献
17.
Palacios F Ochoa de Retana AM Vélez del Burgo A 《The Journal of organic chemistry》2011,76(22):9472-9477
A simple and efficient selective synthesis of 1H-pyrrole-2-phosphine oxides 3 and -phosphonates 7 by addition of enolates derived from acetyl acetates to 2H-azirinylphosphine oxide 1 and -phosphonate 6 is reported. Nucleophilic addition of enolates derived from diethyl malonate to 2H-azirines 1 and 6 led to the formation of functionalized 2-hydroxy-1H-pyrrole-5-phosphine oxide 9 and -phosphonate 10, while vinylogous α-aminoalkylphosphine oxides 14 and -phosphonate 15 may be obtained from azirines and the enolate derived from diethyl 2-phenylmalonate. Ring closure of vinylogous derivatives 14 and 15 in the presence of base led to the formation of 1,5-dihydro-3-pyrrolin-2-ones containing a phosphine oxide 17 or a phosphonate group 18. 相似文献
18.
The reactivity of 5-methyl-4-(pyrrolidin-1-yl)-5H-furan-2-one with aldehydes and with acyl chlorides followed by reduction was studied. The aldol condensation gave predominantly the anti aldol product when the acylation-reduction sequence led exclusively to the syn product. The use of a chiral pyrrolidine, (S)-2-methoxymethylpyrrolidine (SMP), allowed the synthesis of enantio-enriched compounds, the acylation-reduction leading to the (R,R) addition product. 相似文献
19.
S. Narayana Murthy 《Tetrahedron letters》2010,51(28):3649-237
Various 2-amino-4H-chromen-4-yl phosphonate derivatives were synthesized in good yields by condensation of salicylaldehyde, malononitrile or ethylcyanoacetate, and triethyl phosphite using β-cyclodextrin as a reusable catalyst under neutral conditions, in water. 相似文献
20.
Sylvie PaillouxCornel Edicome Shirima Eileen N. DueslerKaren Ann Smith Robert T. Paine 《Polyhedron》2011,30(16):2746-2757
Syntheses for [(diphenylphosphinoyl)methyl]-4,5-dihydrooxazole (2) and [(diarylphosphinoyl)methyl]benzoxazoles [aryl = phenyl (3), tolyl (4), 2-trifluoromethylphenyl (5) and 3,5-bis(trifluoromethyl)phenyl (6)] have been developed. Each ligand has been characterized by spectroscopic methods and single crystal X-ray diffraction analyses have been completed for 2, 3, 4 and 5. The coordination chemistry of the ligands with Nd(NO3)3 and Yb(NO3)3 has been examined and structure determinations for [Nd(2)2(NO3)3(CH3OH)], [Nd(2)2(NO3)3], [Yb(3)2(NO3)3(H2O)]·0.5(CH3OH), [Nd(3)2(NO3)3]·3(CHCl3), [Nd(4)2(NO3)3(H2O)], [Yb(4)2(NO3)3(H2O)] and [Yb(5)2(NO3)3(H2O)]·0.5(CH3CN) are reported. Depending upon conditions, the ligands act as monodentate PO or bidentate, chelating PO,N donors. 相似文献