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Trimethylcyanosilane as a Convenient Reagent for the Preparation of Trimethylsilyl Enol Ethers of 1,3-Diketones
Jin-Cong Zhuo
Molecules , 1999, DOI: 10.3390/41000310
Abstract: Trimethylsilyl enol ethers of 1,3-diketones are generated “in situ” or obtained in high isolated yield by the reaction of 1,3-diketones with trimethylcyanosilane in various solvents such as cyclohexane, hexane, benzene, methylene chloride, chloroform, carbon tetrachloride, and acetonitrile.
Observation of 1,3-Diketones Formation in the Reaction of Bulky Acyl Chlorides with Methyllithium  [PDF]
Jian Zhang,Nianfa Yang,Liwen Yang
Molecules , 2012, DOI: 10.3390/molecules17066415
Abstract: The formation of 1,3-diketones was observed in the reactions of bulky acyl chlorides with methyllithium. The reaction products depend on the steric hindrance around the carbonyl group of the acyl chloride and the electronic effect of the group(s) linked to the carbonyl. When the steric hindrance around the carbonyl group of the acyl chloride is big enough, the 1,3-diketone is the only product. In the case of the moderate hindrance around the carbonyl group of the acyl chloride, a moderate yield of 1,3-diketone is obtained and some tertiary alcohol is generated. When there is no steric hindrance around the carbonyl group of the acyl chloride, the tertiary alcohol is the only product. When the steric hindrance around the carbonyl group is moderate and an electron-donating group is connected to the carbonyl of the acyl chloride, all three products—ketone, 1,3-diketone and tertiary alcohol—can be isolated from the reaction mixture after long reaction times.
Temperature dependence of the Kovats retention indices for alkyl 1,3-diketones on a DB-5 capillary column
DUSAN Z. MIJIN,DUSAN G. ANTONOVIC
Journal of the Serbian Chemical Society , 2004,
Abstract: A series of alkyl 1,3-diketones were used to study the temperature dependence of the Kovats retention indices in the temperature range 130 190 oC (403 463 K). The temperature dependence is described by the empirical equation I = B + B/T + ClnT. On the basis of this equation, the activation enthalpy, DH#, and the chemical potential of the partitioning of one methylene group between the two phases of the chromatographic system, Dmp(CH2), were calculated. Also, the Kovats retention indices boiling point correlations (linear and reciprocal) for alkyl 1,3-diketones were studied and Dmp(CH2) was calculated.
Regioselectivity in the multicomponent reaction of 5-aminopyrazoles, cyclic 1,3-diketones and dimethylformamide dimethylacetal under controlled microwave heating
Kamal Usef Sadek,Ramadan Ahmed Mekheimer,Tahany Mahmoud Mohamed,Moustafa Sherief Moustafa
Beilstein Journal of Organic Chemistry , 2012, DOI: 10.3762/bjoc.8.3
Abstract: The multicomponent reaction of 5-aminopyrazole derivatives with cyclic 1,3-dicarbonyl compounds and dimethylformamide dimethylacetal (DMFDMA) in DMF at 150 °C under controlled microwave heating afforded regioselectively 8,9-dihydropyrazolo[1,5-a]quinazolin-6(7H)-ones 6 rather than the corresponding dihydropyrazolo[5,1-b]quinazolin-8(5H)-ones 4.
Cobalt(II) complexes of tetraazamacrocycles derived from b-diketones and diaminoalkanes
R. N. PRASAD,MITHLESH AGRAWAL,SANJNA SHARMA,SMILJANA RAICEVIC
Journal of the Serbian Chemical Society , 2005,
Abstract: Co(II) complexes of the type [Co(L)(NO3)2] (L = tetraazamacrocycle with 18 to 34-membered ring) were synthesized by the template condensation of b-diketones, such as 2,4-pentanedione, 1-phenyl-1,3-butanedione or 1,3-diphenyl-1,3-propanedione, with diaminoalkanes. The complexes were characterized by elemental analyses, molar conductances and magnetic moments measurements, as well as infra red and electronic spectroscopy.
An Efficient and Chemoselective Method for Oximination of β-Diketones Under Mild and Heterogeneous Conditions  [PDF]
Mohammad Ali Zolfigol
Molecules , 2001, DOI: 10.3390/60800694
Abstract: A combination of oxalic acid dihydrate and sodium nitrite in the presence of wet SiO2 was used as an effective nitrosating agent for the nitrosation of β-diketones to their corresponding α-oximinoketones in moderate to excellent yields under mild and heterogenous conditions.
Photo-Induced Cycloaddition Reactions of α-Diketones and Transformations of the Photocycloadducts  [PDF]
Chengmei Huang,Mengmeng Zheng,Jianhua Xu,Yan Zhang
Molecules , 2013, DOI: 10.3390/molecules18032942
Abstract: Photocycloaddition, along with subsequent transformation of the photocycloadducts, provides expeditious ways to construct various structures. The photo-induced reactions of α-diketones have been reported to proceed via different reaction pathways with the involvement of one or two of the carbonyl groups. Photoinduced reactions of cyclic α-diketones including N-acetylisatin, phenanthrenequinone and isoquinolinetrione with different C=C containing compounds could take place via [2 + 2], [4 + 2] or [4 + 4] photocycloaddition pathways. We have investigated the photoreactions of these cyclic α-diketones with different types of alkenes and alkynes, with a focus on the unusual cascade reactions initiated by the photocycloaddition reactions of these cyclic α-diketones and the applications of these photocycloaddition reactions along with the transformation of the photocycloadducts. In this paper, we discuss the diverse photo-cycloaddition pathways found in the photocycloaddition of o-diones leading to various photocycloadducts and the potential applications of these reactions via further transformation reactions of the adducts.
The solvent free preparation of beta-amino esters alpha,beta-unsaturated ketones and esters with domestic microwave oven
Braibante, Mara E. F.;Braibante, Hugo T. S.;Morel, Ademir F.;Costa, Carla C.;Lima, Marcelo G.;
Journal of the Brazilian Chemical Society , 2006, DOI: 10.1590/S0103-50532006000100026
Abstract: a series of b-amino esters a,b-unsaturated ketones and esters 4a-h and 6a-d derived from a-amino acids have been prepared starting from a-amino esters hydrochorides 2a-d with 1,3- dicarbonyl compounds 3a,b and 5 in presence of triethylamine. these compounds have been prepared under domestic microwave oven, under solvent free condition with and without solid support (k-10 or ksf).
The solvent free preparation of beta-amino esters alpha,beta-unsaturated ketones and esters with domestic microwave oven  [cached]
Braibante Mara E. F.,Braibante Hugo T. S.,Morel Ademir F.,Costa Carla C.
Journal of the Brazilian Chemical Society , 2006,
Abstract: A series of beta-amino esters alpha,beta-unsaturated ketones and esters 4a-h and 6a-d derived from alpha-amino acids have been prepared starting from alpha-amino esters hydrochorides 2a-d with 1,3- dicarbonyl compounds 3a,b and 5 in presence of triethylamine. These compounds have been prepared under domestic microwave oven, under solvent free condition with and without solid support (K-10 or KSF).
Studies on Diazocoupling Products of Dioxomolybdenum (VI) Chelates of β-diketones  [PDF]
M.A. Halim,S.A. Nessa,A.K.L. Rahman,D.A. Chowdhury
Journal of Applied Sciences , 2005,
Abstract: A number of diazocoupling products of molybdenum (VI) chelates of β-diketones with various types of aryldiazonium ions have been prepared. Aryldiazonium ions are obtained through the diazotization of aniline and substituted aniline using sodium nitrite and hydrochloric acid. The prepared diazocoupled products were studied by their analytical data, magnetic moment, molar conductance, electronic, infrared and 1HNMR spectral studies. The presence of vN=N mode in the IR spectra and absence of methane proton signal in the 1HNMR spectra of the prepared diazocoupled products indicate the occurrence of diazocoupling reaction. The molar conductance values indicate the non-electrolytic nature of the diazocoupled products. The electronic spectra and the dia magnetic behavior are indicative of the presence of +6 oxidation state of molybdenum. The structures of the synthesized diazocoupled products of molybdenum (VI) are likely to be octahedral.
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