5400-95-3Relevant academic research and scientific papers
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
, 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.
Influence of substituent on UV absorption and keto-enol tautomerism equilibrium of dibenzoylmethane derivatives
Zawadiak, Jan,Mrzyczek, Marek
, p. 815 - 819 (2012/11/13)
UV absorption spectra of dibenzoylmethane and its 23 derivatives with acetamide, tert-butyl, chloride, fluoride, hydroxyl, methyl, methoxy and nitro substituents in aromatic rings were collected. General influence of substituent on absorption maxima and absorption intensity was defined. Hyperchromic effects were observed for diketones with electron-donating groups in para postion. The keto-enol tautomerism equilibrium constant of obtained compounds was investigated with 1H NMR spectroscopy. Significant changes of equilibrium were observed only for ortho substituted compounds. Results revealed dissimilarity of substituent effects on absorption and keto-enol tautomerism of aromatic β-diketones.
Nucleophilic acylation of α-haloketones with aldehydes: An umpolung strategy for the synthesis of 1,3-diketones
Singh, Santosh,Singh, Pankaj,Rai, Vijai K.,Kapoor, Ritu,Yadav, Lal Dhar S.
experimental part, p. 125 - 128 (2011/02/26)
The first example of N-heterocyclic carbene (NHC)-promoted intermolecular acylation of α-haloketones with aldehydes and α,β-unsaturated aldehydes (enals) is reported. The protocol involves carbonyl umpolung reactivity of aldehydes and enals in which the carbonyl carbon attacks nucleophilically on electrophilic terminal of α-haloketones to afford 1,3-diketones and α,β-unsaturated 1,3-diketones, respectively. Short reaction time, ambient temperature, operational simplicity, and high yields are the salient features of the present procedure.
3,5-Diaryl-1H-pyrazole as a molecular scaffold for the synthesis of apoptosis-inducing agents
Shaw, Arthur Y.,Liau, Hao-Han,Lu, Pei-Jung,Yang, Chia-Ning,Lee, Chien-Hsing,Chen, Jun-Yan,Xu, Zhigang,Flynn, Gary
experimental part, p. 3270 - 3278 (2010/07/08)
The scaffold of 3,5-diaryl-1H-pyrazole was selected as a molecular template to synthesize novel growth-inhibitory agents in the present study. Our findings suggested that analogs bearing electron-withdrawing groups on one ring while electron-donating grou
A novel synthesis of 1,3-diketones by reaction of an α-bromoketone with acyl chlorides promoted by gallium triiodide
Chen, Rener,Wu, Huayue,Zhang, Yongmin
, p. 666 - 667 (2007/10/03)
Promoted by gallium triiodide, an α-bromoketone, bromomethyl phenyl ketone, is treated with acyl chlorides to synthesize 1,3-diketones in good yields under mild and neutral conditions.
Clemmensen reduction. XII The synthesis and acidolysis of some diaryl-substituted cyclopropane-1,2-diols. The possible involvement of a cyclopropyl cation
Davis, Brian R.,Hinds, Mark G.
, p. 309 - 319 (2007/10/03)
The generation of a number of 1,2-diarylcyclopropane-1,2-diols is reported. Reaction of these in situ with acid gives, primarily, an α,β-unsaturated ketone in which the aryl substituent attached to the double bond is that which is best able to stabilize a benzylic cation. It is proposed that the reaction proceeds by O-protonation of the cyclopropane- 1,2-diol, followed by loss of water and opening of the resulting cyclopropyl cation and final deprotonation. Such initial O-protonation contrasts with the C-protonation normally observed in the acidolysis of cyclopropanols and other dialkyl- and alkylaryl-cyclopropane-1,2-diols.
The D parameter (EPR zero-field splitting) of localized 1,3-cyclopentanediyl triplet diradicals as a measure of electronic substituent effects on the spin densities in para-substituted benzyl-type radicals
Adam, Waldemar,Kita, Fumio,Harrer, Heinrich M.,Nau, Werner M.,Zipf, Rainer
, p. 7056 - 7065 (2007/10/03)
The zero-field splitting parameters D of the symmetrically disubstituted and unsymmetrically monosubstituted 1,3-diaryl-1,3-cyclopentanediyl triplet diradicals 1, 2 (X = p-MeO, p-Me, p-Cl, P-NH2, P-CO2Me, p-CN, p-NO2), and 5 were determined in 2-methyltetrahydrofuran glass at 77 K. The linear plot (m = 0.558, r2 = 0.993) of the experimental D values for the symmetrically disubstituted derivatives versus the corresponding monosubstituted ones reveals that the electronic substituent effects are additive and implies (except for the magnetic dipolar interaction) that each benzyl-type radical site acts independently in the localized diradicals. This additivity permits us to view these triplet diradicals as a composite of the two separate monoradical components and allows us to assess valuable electronic properties of benzyl-type monoradicals from the D parameter of the triplet diradical species. A theoretical analysis shows that the D parameter is a measure of the spin density p at the benzylic positions and the inter-radical distance d in localized diradicals. A good correlation exists between the D parameter of these triplet diradicals (constant inter-radical distance d) and the EPR hyperfine coupling constants of the corresponding benzyl-type monoradicals, which establishes that the observed electronic substituent effects reflect changes in the spin densities at the radical sites. The novel AZ? scale allows us to quantify spectroscopically the para substituent effect on the spin delocalization at the benzylic position.
A new route for the synthesis of 1,3-diketones
Zanina, A. S.,Shergina, S. I.,Sokolov, I. E.,Myasnikova, R. N.
, p. 689 - 694 (2007/10/02)
A simple route for the synthesis of 1,3-diketones by the reaction of acetylenic ketones with amines followed by hydrolysis of the resulting aminovinylketones is siggested. - Key words: acetylenic ketones; 1,3-diketones; aminovinylketones; synthesis.
STRUCTURE OF THE PRODUCTS OF THE REACTION OF 5,6-DIAMINO-1,3-DIMETHYLURACIL WITH 1,3-DIARYL-2,3-DIHALOPROPANONES
Kolos, N. N.,Shishkin, O. V.,Orlov, V. D.,Struchkov, Yu. T.
, p. 485 - 491 (2007/10/03)
The reaction of 5,6-diamino-1,3-dimethyluracil with α,β-dihalopropanones gives only β-(5-imino-6-amino-1,3-uracil)chalcones.An x-ray diffraction structural analysis was carried out for one of these products.
The Acid-catalyzed Decomposition of α-Diazo β-Hydroxy Ketones
Miyauchi, Kazuo,Hori, Kimiaki,Hirai, Tsuguji,Takebayashi, Matsuji,Ibata, Toshikazu
, p. 2142 - 2146 (2007/10/02)
The proton acid-catalyzed decomposition of 3-aryl-2-diazo-3-hydroxy-1-phenylpropanone (1) gave aryl and hydrogen migration products.The former was the enol-form (2) of 2-aryl-3-phenyl-1,3-propanedione and the latter was the enol- (3) and keto-form (4) of 1-aryl-3-phenyl-1,3-propanedione.The product ratios, 2/(3+4), were affected by the catalysts and solvents used.More polar solvents favored the formation of aryl migration products (2).On the other hand, the BF3-catalyzed decomposition of 1 gave acetylenic ketones as main products along with 2, 3, 4.The TsOH-catalyzed decomposition of 2-diazo-3-hydroxy-3-phenyl-1-indanone, (cyclic α-diazo β-hydroxy ketone), gave 2-phenyl-1,3-indandione quantitatively through phenyl migration.
