55489-05-9Relevant academic research and scientific papers
Metal-Organic Architectures Assembled from Multifunctional Polycarboxylates: Hydrothermal Self-Assembly, Structures, and Catalytic Activity in Alkane Oxidation
Gu, Jinzhong,Wen, Min,Cai, Yan,Shi, Zifa,Arol, Aliaksandr S.,Kirillova, Marina V.,Kirillov, Alexander M.
, p. 2403 - 2412 (2019/02/28)
A three-component aqueous reaction system comprising copper(II) acetate (metal node), poly(carboxylic acid) with a phenylpyridine or biphenyl core (main building block), and 1,10-phenanthroline (crystallization mediator) was investigated under hydrothermal conditions. As a result, four new coordination compounds were self-assembled, namely, {[Cu(μ3-cpna)(phen)]·H2O}n (1), {[Cu(μ-Hbtc)(phen)]·H2O}n (2), {[Cu(μ3-Hcpic)(phen)]·2H2O}n (3), and [Cu6(μ-Hcptc)6(phen)6]·6H2O (4), where H2cpna = 5-(2′-carboxylphenyl)nicotinic acid, H3btc = biphenyl-2,4,4′-tricarboxylic acid, H3cpic = 4-(5-carboxypyridin-2-yl)isophthalic acid, H3cptc = 2-(4-carboxypyridin-3-yl)terephthalic acid, and phen = 1,10-phenanthroline. Crystal structures of compounds 1-3 reveal that they are 1D coordination polymers with a ladder, linear, or double-chain structure, while product 4 is a 0D hexanuclear complex. All of the structures are extended further [1D a?' 2D (1 and 2), 1D a?' 3D (3), and 0D a?' 3D (4)] into hydrogen-bonded networks. The type of a multicarboxylate building block has a considerable effect on the final structures of 1-4. The magnetic behavior and thermal stability of 1-4 were also investigated. Besides, these copper(II) derivatives efficiently catalyze the oxidation of cycloalkanes with hydrogen peroxide under mild conditions. The obtained products are the unique examples of copper derivatives that were assembled from H2cpna, H3btc, H3cpic, and H3cptc, thus opening up their use as multicarboxylate ligands toward the design of copper-organic architectures.
Efficient and selective oxidation of methyl substituted cycloalkanes by heterogeneous methyltrioxorhenium-hydrogen peroxide systems
Bianchini, Gianluca,Crucianelli, Marcello,Canevali, Carmen,Crestini, Claudia,Morazzoni, Franca,Saladino, Raffaele
, p. 12326 - 12333 (2007/10/03)
Polymer-supported methyltrioxorhenium (MTO) systems are efficient catalysts for the oxidative functionalisation of cyclohexane and cyclopentane derivatives with H2O2 as oxygen donor. Using poly(4-vinyl)pyridine and poly(4-vinyl)pyridine-N-oxide as MTO supports, cycloalkanol, cycloalkanediol, cycloalkanone and ω-hydroxy methyl ketone derivatives were obtained in different yields depending on the experimental conditions. Interestingly, cycloalkane dimers were selectively recovered in acceptable to good yields when the oxidation was performed with polystyrene-microencapsulated MTO catalyst. The EPR investigation suggests that the homolytic cleavage of the CH3-Re bond with formation of CH3{radical dot} radicals occurs inside the polystyrene capsule, indicating a possible role of methyl radical in the cycloalkane dimerisation pathway.
Intercalation of multiple carbon atoms between the carbonyls of α-diketones
Balskus,Mendez-Andino,Arbit,Paquette
, p. 6695 - 6704 (2007/10/03)
The reaction of open-chain or cyclic α-diketones with specific ω-alkenyl organometallics leads readily under the proper conditions to 1,2-diols bonded to terminal olefinic chains. With 1-phenyl-1,2-propanedione, biacetyl, and cyclohexane-1,2-dione, allylindation in aqueous THF proceeds readily at both adjacent carbonyls. For cyclododecane-1,2-dione, recourse must be made to allylmagnesium bromide for completing the second-stage condensation. Grignard reagents have also served well as reactants for biacetyl monoadducts. In contrast, monoallylated camphorquinone is reluctant to couple to Grignard reagents and reacts only when Barbier-type alkyllithium reactions are applied. The ring closing metatheses of these products have been examined. Where six-membered ring formation operates, cyclization can be performed directly on diols. When larger rings are involved, the diols will react only if structural preorganization capable of facilitating mutual approach of the two double bonds is at play. For this purpose, the prior conversion to a cyclic carbonate holds considerable utility. In the latter setting, saponification must precede the diol cleavage step which has been performed with lead tetraacetate. The latter reagent also exhibits the very beneficial effect of facilitating removal of ruthenium and phosphorus byproducts generated during the metathesis step. This chemistry conveniently lends itself to the controlled intercalation of multiple methylene groups between the carbonyl carbons of readily available α-diketones to deliver linear or cyclic products.
Efficient method for the preparation of pinacols derived from aromatic and aliphatic ketones by using low-valent titanium reagents in dichloromethane-pivalonitrile
Kagayama,Igarashi,Mukaiyama
, p. 657 - 665 (2007/10/03)
The reductive coupling reaction of aldehydes and ketones, including unsymmetrical aliphatic ketones, proceeded smoothly to give the corresponding pinacols in good to high yields under mild conditions by using combination of titanium(II) chloride and zinc or titanium(IV) chloride and zinc in dichloromethane-pivalonitrile. Meso-selective formation of the coupling products was observed in the cases of some aliphatic ketones. The diastereoselectivities of coupling products depend on both difference of bulkiness of 2-, and 2'-substituents of carbonyl group of the reactant, and overall steric effect around the carbonyl groups.
Tandem deployment of indium-, ruthenium-, and lead-promoted reactions. Four-carbon intercalation between the carbonyl groups of open-chain and cyclic α-diketones
Mendez-Andino, Jose,Paquette, Leo A.
, p. 1263 - 1265 (2007/10/03)
(equation presented) An efficient strategy for the conversion of 1,2-diketones into saturated 1,6-diketones and Δ2,3/Δ3,4-unsaturated congeners thereof is reported.
