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1.
Copper-catalyzed sulfonylation of alkynes using sodium sulfinates in air produced regio- and stereoselectively (E)-alkenyl sulfones. When a CuCl catalyst was employed, the hydrosulfonylation proceeded syn-selectively, and (E)-alkenyl sulfones were synthesized in excellent yields. In contrast, the reaction using CuI catalyst produced (E)-β-haloalkenyl sulfones anti-selectively in the presence of potassium halides. Furthermore, the (E)-β-bromoalkenyl sulfones are possible to convert into various alkenyl sulfones by Suzuki–Miyaura coupling. 相似文献
2.
A new approach to the synthesis of pyrrolidine, tetrahydrofuran, and imidazolidin-2-one via N-heterocyclic carbene–gold(I)-catalyzed intramolecular amino- or oxyarylation reactions from a wide variety of alkene substrates such as N-allyl amides, alcohols, carboxylic acids, and ureas in the presence of Selectfluor under mild conditions has been developed. 相似文献
3.
Rh-Catalyzed asymmetric 1,4-selective addition of arylboronic acids to β,γ-unsaturated α-keto ester was developed using chiral tert-butanesulfinylphosphine as ligand, good yields (up to 87%), good 1,4-regioselectivities (up to 96:4), and high enantioselectivities (up to 94% ee) were achieved. 相似文献
4.
O. O. Shyshkina K. S. Popov O. O. Gordivska T. M. Tkachuk N. V. Kovalenko T. A. Volovnenko Yu. M. Volovenko 《Chemistry of Heterocyclic Compounds》2011,47(8):923-945
Published data on the synthesis and chemical properties of dihydrothiophen-3(2H)-one 1,1-dioxide, dihydro-2H-thiopyran-3(4H)-one 1,1-dioxide, 1-benzothiophen-3(2H)-one 1,1-dioxide, and 1H-isothio-chromen-4(3H)-one 2,2-dioxide are reviewed. The choice of subjects was based on the presence of identical structural fragments, carbonyl,
active methylene, and sulfonyl groups. 相似文献
5.
The α-alkylidene β-ketoesters 2-carbethoxycyclopentenone (1a) and ethyl 2-benzoylacrylate (1b) react with 1,2-dimethylbutadiene (2) (Diels-Alder), N-benzyl-N-(cyclohexylethynyl)-4-methylbenzenesulfonamide (3) (Ficini reaction), ethynyl(phenyl)sulfane (4) ([2 + 2] cycloaddition), and 1,2,5-trimethyl-1H-pyrrole (5) (Michael addition) in the presence of copper(I) (6) or copper(II) triflate (7) (1-2 mol %) in dichloromethane. This convenient protocol converts 1a and 1b to the corresponding cycloaddition (8-10) or Michael addition (11) products in good yields after reaction times of 0.5-3 h without requiring purified solvents or inert gas atmosphere. 相似文献
6.
Yamamoto Y Shirai T Watanabe M Kurihara K Miyaura N 《Molecules (Basel, Switzerland)》2011,16(6):5020-5034
A ruthenium-catalyzed asymmetric arylation of aliphatic aldehydes and α-ketoesters with arylboronic acids has been developed, giving chiral alkyl(aryl)methanols and α-hydroxy esters in good yields. The use of a chiral bidentate phosphoramidite ligand (Me-BIPAM) achieved excellent enantioselectivities. 相似文献
7.
Andreas Petri Oliver SeidelmannUwe Eilitz Frank LeßmannStefan Reißmann Volkmar WendischAndrey Gutnov 《Tetrahedron letters》2014
Asymmetric conjugate addition of arylboronic acids to 2-nitroacrylamide in the presence of cationic palladium–Chiraphos complex proceeds with high yield and enantioselectivity (73–89% ee) using as low as 0.05–0.25 mol % of the catalyst. The adducts can be smoothly transformed into the corresponding β2-homophenylglycines in two simple steps. 相似文献
8.
Aleksey A. Goldberg Aleksey V. Shastin Valentine G. Nenajdenko 《Journal of fluorine chemistry》2010,131(3):384-5688
CF3CFBr2 was employed in catalytic olefination reactions of aromatic aldehydes. In situ prepared hydrazones of aldehydes were transformed to β-fluoro-β-(trifluoromethyl)styrenes by reaction with CF3CFBr2 under CuCl catalysis. Based on this reaction, a novel stereoselective approach towards β-fluoro-β-(trifluoromethyl)styrenes was elaborated. Nucleophilic vinylic substitution of fluorine by secondary amines, thiolates and alkoxides in β-fluoro-β-(trifluoromethyl)styrenes was also tested. 相似文献
9.
A new paradigm of the oxidative decarboxylative sulfono functionalization of cinnamic acids with sulfinate salts mediated by K2S2O8 under aerobic conditions to afford synthetically and biologically relevant β-keto sulfones has been described. It is the first report on the transition-metal-free synthesis of β-keto sulfones from cinnamic acids, which employs environmentally benign, readily available and inexpensive starting materials and oxidants, viz. air and K2S2O8. 相似文献
10.
11.
Treatment of β-keto sulfones with terminal alkynes gave unsaturated δ-keto sulfones in good to excellent yields under rhenium catalysis. In this reaction, the insertion of the alkynes into the nonstrained carbon-carbon single bond between the α- and β-positions of the β-keto sulfones proceeded smoothly, and (Z)-isomers were produced with high regio- and stereoselectivities. 相似文献
12.
《Tetrahedron: Asymmetry》1999,10(7):1369-1380
A series of β-hydroxy sulfones were synthesized with high enantioselectivities via a new enantioselective ruthenium-catalyzed hydrogenation using MeO-BIPHEP as a ligand. Some β-hydroxy sulfones were used in the synthesis of optically active butenolides and γ-butyrolactones with high yields and enantioselectivities over 95%. 相似文献
13.
A rhodium-catalyzed asymmetric 1,2-addition of arylboronic acids to isatins with chiral sulfur–alkene hybrid ligands was achieved, and a variety of 3-aryl-3-hydroxy-2-oxindoles were obtained in moderate to good yields with up to 85% ee and a biologically active compound was synthesized with this strategy. 相似文献
14.
A practical and straightforward approach for the highly stereoselective synthesis of β-amino sulfones was developed. With lithium bis(trimethylsilyl)amide as the base, the corresponding sulfone-stabilized carbanion derived from alkylphenyl sulfone can be transferred to N-(tert-butylsulfinyl) aldimines in excellent yields and with high diastereoselectivity. 相似文献
15.
《中国化学快报》2020,(6)
Herein,we report the first Rh~Ⅲ-catalyzed regioselective C8 arylation of quinoline N-oxides with commercially available arylboronic acids as coupling partners.This procedure is simple,and the reaction shows perfect regioselectivity,a broad substrate scope,and isolated yields of up to 92%.We demonstrate the utility of the reaction by using it for late-stage functionalization of a fungicide. 相似文献
16.
《Journal of fluorine chemistry》1987,36(1):41-47
Pentafluoroanilides of acetoacetic and benzoylacetic acids and their α-SCF3 substituted analogues have been synthesized from the respective β-keto esters. Cu(II) complexes of the compounds obtained as well as of anilide of α-(trifluoromethylthio)acetoacetic acid have been prepared and characterized. The structure of these compounds has been elucidated on the basis of the elemental analysis and IR, MS, 1H and 19F NMR spectra. 相似文献
17.
Nickel(I) complexes were generated in situ from Ni (PPh3)2Cl2 using activated iron and the complexes combined with N,N′-bis(4-fluorobenzylidene) ethane-1,2-diamine (BFBED) were then used as a catalyst for the 1,4-addition reaction of arylboronic acids to α,β-unsaturated substrates. The reaction proceeded to completion and did not require the addition of a base but the addition of potassium iodide is crucial to this cross-coupling reaction. Moreover, experimental observations suggested a possible Ni(I)–Ni(III) catalytic cycle mechanism. 相似文献
18.
Ligand-free copper(Ι)-catalyzed Sonogashira-type coupling of arylboronic acids with terminal alkynes
Changduo Pan 《Tetrahedron letters》2009,50(35):5044-807
An efficient ligand-free CuI-catalyzed Sonogashira-type coupling reaction of arylboronic acids with terminal alkynes under air is described. The electron-deficient alkynes gave the desired cross-coupling products in good yields. Thus, it represents a simple and alternative method for the traditional Sonogashira reaction. 相似文献
19.
Zhi-Tao HeYa-Bing Wei Hong-Jie YuCai-Yun Sun Chen-Guo FengPing Tian Guo-Qiang Lin 《Tetrahedron》2012,68(45):9186-9191
Utilizing toluene/isopropanol (20:1 to 40:1) as a solvent and KHF2 as an additive, the rhodium/diene-catalyzed asymmetric arylation (RCAA) reaction of arylboronic acids to N-Boc-protected α,β-unsaturated δ-lactam proceeded smoothly to afford chiral 4-aryl-2-piperidinones with high to excellent yields (up to 94%) and enantioselectivities (up to >99% ee). Further conversion of adduct (R)-1-(tert-butyloxycarbonyl)-4-(4-chlorophenyl)-2-piperidone to (R)-Homobaclofen hydrochloride was also presented. 相似文献
20.
Fuzhong HanJun Chen Xiangyang ZhangJibing Liu Linfeng CunJin Zhu Jingen DengJian Liao 《Tetrahedron letters》2011,52(7):830-833
Efficient Rh-catalyzed asymmetric 1,4-addition of arylboronic acids to ethyl-γ-phthalimidocrotonate by using bis-sulfoxide ligand affords γ-aminobutyric acid (GABA) derivatives with high enantioselectivities (90-96% ee) under mild conditions. Optically pure (S)-Baclofen and (S)-Rolipram have been prepared successfully through this synthetic route. 相似文献