119-61-9Relevant academic research and scientific papers
Substituent and Solvent Effects in the Reactions of Diaryldiazomethanes with 2,3-Dichloro-5,6-dicyanobenzoquinone
Oshima, Takumi,Nagai, Toshikazu
, p. 2039 - 2044 (1981)
Kinetic studies have been made of the reactions of fifteen meta- and para-substituted diphenyldiazomethanes(DDMs) with 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) in benzene.The second order rate constants, k, increased with the electron-donability of the substituents, and the value could be correlated with the Yukawa-Tsuno equation: log k/k0 = -2.33(?0 + 0.47Δ+) + 0.017, (r = 0.996, 30 deg C).The ρ value, -2.33, indicates the development of a positive charge at the diazo carbon in the transition state, while the R value, 0.47, confirms the moderate stabilization of the positive charge by the ?-electronic contribution of the para substituents.The rate constants have also been determined for the reaction of diphenyldiazomethane(DDM) with DDQ in 28 aprotic solvents.The effects of solvents can be interpreted in terms of the basicity and the steric nature of the solvents.The products of these reactions were poly(2,3-dichloro-5,6-dicyanohydroquinone benzhydryl ether)s, which were easily convertible into benzophenones and α,α-dimethoxydiphenylmethane, together with 2,3-dichloro,5,6-dicyanohydroquinone, under the influence of water and methanol.These solvolysis products were also obtained in excellent yields in the initial presence of these additives.
COMPARISON OF PHOTOINDUCED ELECTRON TRANSFER REACTIONS OF AROMATIC CARBONYL VS. CYANO COMPOUNDS WITH ELECTRON DONORS IN CONDENSED PHASE: THE IMPORTANCE OF THE SPIN STATE OF THE GEMINATE ION PAIR FOR OBTAINING HIGH ION YIELDS.
Haselbach, Edwin,Vauthey, Eric,Suppan, Paul
, p. 7335 - 7344 (1988)
Photoinduced electron transfer reactions in acetonitrile with benzophenone, anthraquinone, 9-cyanoanthracene and 9,10-dicyanoanthracene as electron acceptors, and with 1,4-diazabicyclooctane and N,N-dimethylaniline as electron donors have been studied with ns-laser flash photolysis and fluorescence quenching measurements.For these systems the resulting free ion yield depends on the spin state of the geminate ion pair: its separation is very efficient if formed in a triplet state (carbonyl compounds/donors), while it is very inefficient if formed in a singlet state (cyanoantracenes/donors).In the triplet systems, geminate back electron transfer is limited by the rate of spin flip.
Oxovanadium(v)-catalyzed deoxygenative homocoupling reaction of alcohols
Sakuramoto, Takashi,Donaka, Yosuke,Tobisu, Mamoru,Moriuchi, Toshiyuki
, p. 17571 - 17576 (2019)
Oxovanadium(v)-catalyzed transformation of alcohols in the presence of hydrazine derivatives was demonstrated. The direct hydrazination reaction of 1,3-diphenylprop-2-en-1-ol with 1,1-diphenylhydrazine in the presence of VO(OSiPh3)3 as a catalyst and MS3A as a dehydrating reagent proceeded to afford the corresponding hydrazination product. On the contrary, the utilization of 1,1-dimethylhydrazine instead of 1,1-diphenylhydrazine was found to induce the deoxygenative homocoupling reaction of the allyl alcohol to give the corresponding 1,5-diene as a major product. In addition to the deoxygenative homocoupling product, the allyl amine into which aniline was introduced was also obtained by using 1,2-diphenylhydrazine in the reaction of 1,3-diphenyl-2-methylprop-2-en-1-ol. Oxovanadium(v)-catalyzed deoxygenative homocoupling reaction of benzyl alcohols could also be performed in the presence of 1,1-dimethylhydrazine.
Ligand-free palladium-catalyzed aerobic oxidative coupling of carboxylic anhydrides with arylboronic acids
Yin, Weiyan,He, Haifeng,Zhang, Yani,Long, Tong
, p. 2402 - 2406 (2014)
We report a new, effective and environmentally friendly protocol for selective aerobic oxidative coupling of arylboronic acids with carboxylic anhydrides in the presence of ligand-free palladium catalyst. The aryl benzoates are obtained in good to excellent yields.
Co(ii)-cluster-based metal-organic frameworks as efficient heterogeneous catalysts for selective oxidation of arylalkanes
Fan, Yanru,Li, Xiao,Gao, Kuan,Liu, Yu,Meng, Xiangru,Wu, Jie,Hou, Hongwei
, p. 1666 - 1673 (2019)
To explore metal-organic frameworks (MOFs) based on Co-clusters as heterogeneous catalysts to selectively catalyze the reaction of C-H bond oxidation of aromatic alkanes to their corresponding ketones, three MOFs {[Co5(pmbcd)2(μ3-OH)2(H2O)4(DMF)2]·4DMF}n (MOF 1), {[Co2(pmbcd)(bpea)2]·2H2O·2DMF}n (MOF 2), and {[Co2(pmbcd)(dpp)2]·3H2O·2DMF}n (MOF 3) (H4pmbcd = 9,9′-(1,4-phenylenebis(methylene))bis(9H-carbazole-3,6-dicarboxylic acid), bpea = 1,2-bis(4-pyridyl)ethane, dpp = 1,3-di(4-pyridyl)propane) were successfully synthesized and structurally characterized. MOF 1 was constructed from a pentanuclear Co(ii) cluster and exhibited a porous framework with channels of 8 × 10 ?2 along the b axis. MOF 2 was constructed from [Co2(CO2)4] units and presented a porous three-dimensional (3D) framework with channels of 11 × 13 ?2 along the b axis and of 10 × 12 ?2 along the c axis. MOF 3 was a flat two-dimensional (2D) layer based on binuclear Co(ii) units when dpp as an auxiliary ligand was introduced. The Co5-cluster-based MOF 1 exhibited excellent catalytic activity for the direct C-H bond activation of arylalkanes to ketones in H2O under room temperature because of its high density of Lewis acidic sites within the frameworks and suitable channel size to access the catalytic sites. It also presented the spatial confinement effect and catalyzed the reaction with high regioselectivity, forming mono-ketones as the sole products. Easy product separation, simple reaction procedures, and recyclability of these catalysts make the catalytic system attractive. Our work highlights the superiority of the MOF-based materials as heterogeneous catalysts.
Oxidation of phenylhydrazones of α-keto esters with hypervalent organoiodine reagents
Barton, Derek H. R.,Jaszberenyi, Joseph Cs.,Shinada, Tetsuro
, p. 7191 - 7194 (1993)
α-Ketoacids and ketones can easily be regenerated in high yield from their phenylhydrazones via hydroxy azo compounds upon oxidation with hupervalent iodine reagents.
Ionic liquid [bmim]Br assisted chemoselective benzylic [Formula presented] oxidations using tert-butyl hydroperoxide
Naidu, Shivaji,Reddy, Sabbasani Rajasekhara
, p. 441 - 445 (2016)
A mild and efficient, ionic-liquid-assisted green protocol for the chemoselective oxygenation of benzylic C-H bonds to corresponding ketones using ionic liquid [bmim]Br with tert-butyl hydroperoxide has been developed. The method reported in this paper has the advantages of [bmim]Br acting as recyclable solvent and reagent. The usage of additives such as acids or bases and metal salts is not required. The developed strategy is further extended to oxidation of secondary alcohols to respective ketones under similar optimized reaction conditions.
Mechanism of thermal decomposition of diphenyldiazomethane in the presence of oxygen
Komissarov,Nazarov,Yamilova
, p. 261 - 264 (1997)
The kinetics, products, and mechanism of thermal decomposition of diphenyldiazomethane (RN2, R = Ph2C) in the presence of oxygen were studied. Thermolysis is accompanied by chemiluminescence. An-emitter of chemiluminescence (3RO) forms in the reaction of benzophenone 0-oxide ROO with RN2.
Thiol ester-boronic acid cross-coupling. Catalysis using alkylative activation of the palladium thiolate intermediate
Savarin, Cecile,Srogl, Jiri,Liebeskind, Lanny S.
, p. 3229 - 3231 (2000)
(matrix presented) Thiol esters and boronic acids do not participate in cross-coupling in the presence of palladium catalysts. However, efficient palladium-catalyzed thiol ester-boronic acid cross-coupling is observed when simple alkylating agents are present. Alkylative conversion of the very stable palladium-thiolate bond to a labile palladium-thioether bond is presumed to be crucial to the catalysis. Of the systems studied, 4-halo-n-butyl thiol esters were most effective in this cross-coupling.
Kinetics, products, and mechanism of the reaction of diphenylcarbonyl oxide with sulfoxides
Nazarov,Chainikova,Krupin,Khursan,Kalinichenko,Komissarov
, p. 1496 - 1500 (2000)
The kinetics of the reactions of diphenylcarbonyl oxide with dimethyl, di-n-hexyl, diphenyl, dibenzyl, and n-hexylbenzyl sulfoxides in acetonitrile was studied by flash photolysis at 295 K. The oxidation of sulfoxide affords the corresponding sulfone as t
