1138-14-3Relevant academic research and scientific papers
Synthesis and Reactions of 1,3,4,6-Tetra-2-thienylthienothiophene
Ishii, Akihiko,Nakayama, Juzo,Kazami, Jun-ichi,Ida, Yutaka,Nakamura, Takao,Hoshino, Masamatsu
, p. 78 - 82 (1991)
1,3,4,6-Tetra-2-thienylthienothiophene (1f) was synthesized from di-2-thenoylmethane after five steps.The cycloaddition reaction of 1f with N-phenylmaleimide yielded a pair of exo (major) and endo (minor) adducts 7 and 8, whose structures were assigned on the basis of the difference in the reactivity toward m-chloroperbenzoic acid.The reaction of 1f with phenyl vinyl sulfoxide, dimethyl acetylenedicarboxylate, and di-2-thenoylacetylene gave benzothiophene derivatives 13, 15, and 16, respectively.
Structure and reactivity of bis(iodozincio)methane solution
Matsubara, Seijiro,Yoshino, Hideaki,Yamamoto, Yuhei,Oshima, Koichiro,Matsuoka, Hideki,Matsumoto, Kozo,Ishikawa, Kazuhiko,Matsubara, Eiichiro
, p. 5546 - 5551 (2005)
Bis(iodozincio)methane, which has been shown to be an efficient reagent for organic synthesis, is obtained as THF solution. The structural information about the reagent as THF solution was corrected by small angle neutron scattering and by anomalous X-ray scattering. Those scattering experiments implied that the prepared bis(iodozincio)methane exists without forming any oligomer or aggregate. A coordination of tetrahydrothiophene to bis(iodozincio)methane enhances the nucleophilicity of the reagent and stabilizes its monomeric structure in the solution.
Regioselective Rhodium-Catalyzed Addition of 1,3-Dicarbonyl Compounds to Terminal Alkynes
Beck, Thorsten M.,Breit, Bernhard
, p. 124 - 127 (2016)
A new method for the rhodium-catalyzed regioselective C-C bond formation using terminal alkynes and 1,3-dicarbonyl compounds to achieve valuable branched α-allylated 1,3-dicarbonyl products is reported. With a Rh(I)/DPEphos/p-CF3-benzoic acid as the catalyst system, the desired products can be obtained in good to excellent yields and with perfect regioselectivity. A broad range of functional groups were tolerated, and first experimental insights of a plausible reaction mechanism were obtained.
Steady state and laser photolysis studies of keto-enol tautomerizations in 2-alkyl-1,3-diketones having five-membered rings in acetonitrile: Temporal UV-A sunscreen
Suwa, Yurie,Yamaji, Minoru
, p. 69 - 74 (2016)
Keto-enol tautomerization in 2-alkyl-1,3-diketons having five-membered rings was studied using steady state and laser flash photolysis techniques in solution. The alkyl keto-diketones undergo photoinduced tautomerization mainly in the triplet state to the enol in acetonitrile. The alkyl enol-diketones, thus formed, undergo thermal tautomerization to the original keto forms in a few days. The alkyl enol-diketones show fast internal conversion from the excited singlet state to the ground state without yielding the corresponding isomeric forms (rotamer). Based on the computation for state energies of the keto, enol and isomer forms, a schematic energy diagram for the tautomerization was drawn.
Thiophene based europium β-diketonate complexes: Effect of the ligand structure on the emission quantum yield
Freund, Christelle,Porzio, William,Giovanella, Umberto,Vignali, Francesco,Pasini, Mariacecilia,Destri, Silvia,Mech, Agnieszka,Di Pietro, Sebastiano,Di Bari, Lorenzo,Mineo, Placido
, p. 5417 - 5429 (2011)
The synthesis and the molecular and photophysical characterization, together with solid state and solution structure analysis, of a series of europium complexes based on β-diketonate ligands are reported. The Eu(III) complex emission, specifically its photoluminescence quantum yield (PL-QY), can be tuned by changing ligands which finely modifies the environment of the metal ion. Steady-state and time-resolved emission spectroscopy and overall PL-QY measurements are reported and related to geometrical features observed in crystal structures of some selected compounds. Moreover, paramagnetic NMR, based on the analogous complexes with other lanthanides, are use to demonstrate that there is a significant structural reorganization upon dissolution, which justifies the observed differences in the emission properties between solid and solution states. The energy of the triplet levels of the ligands and the occurrence of nonradiative deactivation processes clearly account for the luminescence efficiencies of the complexes in the series.
Method for synthesizing 1, 3-dicarbonyl compound based on terminal alkyne and acyl halide by one-pot process
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Paragraph 0069-0074; 0087-0089, (2020/07/21)
The invention belongs to the technical field of catalytic synthesis, and discloses a method for synthesizing a 1, 3-dicarbonyl compound by a one-pot process, and the method comprises the following steps: by using simple palladium and copper salts as catalysts, reacting terminal alkyne with acyl halide at 0-80 DEG C for 0.5-12 hours under the action of trifluoromethanesulfonic acid to obtain the 1,3-dicarbonyl compound, wherein the molar ratio of the terminal alkyne to the acyl halide to the palladium salt to the copper salt to the trifluoromethanesulfonic acid is 1 to (1 to 2) to (0.00001 to0.10) to (0.00001 to 0.10) to (0.00004 to 0.40); the catalysts used in the method are common the commercialized palladium salt and copper salt, reagents used in the reaction are commercialized reagents, in addition, the raw materials are cheap and easy to obtain, functional group tolerance is good, reaction conditions are mild, operation is easy and convenient, and atom economy is high.
Determination of the enol form of asymmetric 1,3-dicarbonyl compounds: 2D HMBC NMR data and DFT calculations
Tan, Meltem,Bildirici, Ishak,Menges, Nurettin
, p. 953 - 968 (2018/10/02)
In this study, a series of asymmetric aryl 1,3-dicarbonyl compounds were synthesized and their enol forms were observed via experimental data and theoretical calculations. According to the 1H-and 13C-NMR results, all the investigated compounds were found
2,2-Difluoro-1,3-diketones as gem-Difluoroenolate Precusors for Asymmetric Aldol Addition with N-Benzylisatins
Qian, Jinlong,Yi, Wenbin,Huang, Xin,Jasinski, Jerry P.,Zhang, Wei
, p. 2811 - 2816 (2016/09/13)
2,2-Difluoro-1,3-diketones are introduced as gem-difluoroenolate precursors for the first example of an organocatalytic asymmetric aldol addition with N-benzylisatins to form 3-difluoroalkyl-3-hydroxyoxindoles. (Figure presented.).
Transition-metal-free formal decarboxylative coupling of ?±-oxocarboxylates with ?±-bromoketones under neutral conditions: A simple access to 1,3-diketones
He, Zhen,Qi, Xiaotian,Li, Shiqing,Zhao, Yinsong,Gao, Ge,Lan, Yu,Wu, Yiwei,Lan, Jingbo,You, Jingsong
supporting information, p. 855 - 859 (2015/02/05)
A transition-metal-free formal decarboxylative coupling reaction between ?±-oxocarboxylates and ?±-bromoketones to synthesize 1,3-diketone derivatives is presented. In this reaction, a broad scope of substrates can be employed, and neither a metal-based reagent nor an additional base is required. DFT calculations reveal that this reaction proceeds through a coupling followed by decarboxylation mechanism and the ?±-bromoketone unprecedentedly serves as a nucleophile under neutral conditions. The rate-determining step is an unusual hydrogen-bond-assisted enolate formation by thermolysis.
Diastereoselective nucleophilic cyclopropanation of 1,2-diketones and α-ketoimines with bis(iodozincio)methane
Nomura, Kenichi,Asano, Keisuke,Kurahashi, Takuya,Matsubara, Seijiro
experimental part, p. 1381 - 1399 (2009/07/17)
A reaction of 1,2-diketones and α-ketoimines with bis(iodozincio)methane gave cyclopropan-1,2-diol and 2-aminocyclopropanol respectively via nucleophilic [2+1]cycloaddition. The reaction proceeded via a sequential nucleophilic attack of the dizinc reagent to vicinal two carbonyl group. The reaction showed high diastereoselectivity to give cis-isomer via a face-to-face coordination between the substrate and bis(iodozincio)methane.
