101-81-5Relevant articles and documents
Application of a dimeric P,C-palladacycle complex as a catalyst in Suzuki and Heck cross-coupling reactions
Karami, Kazem,Ghasemi, Mahdiyeh,Naeini, Nasrin Haghighat
, p. 1352 - 1355 (2013)
In this Letter the dimeric palladacycle [Pd(μ-C1)(P (OPh) 2(OC6H4)]2 containing a phosphorus donor atom is prepared and its catalytic activity was tested in the Suzuki reaction of phenylboronic acid at room temperature, and the Heck reaction of styrene at 130 °C with aryl halides of varying electron density. All reactions were monitored by GC and generally gave high yields of coupled products. Copyright
Hypovalent Radicals. 6. Electroreduction of Diazodiphenylmethane-Intermediacy of Ph2CN-. and PhC-.
McDonald, Richard N.,Triebe, F. M.,January, J. R.,Borhani, K. J.,Hawley, M. D.
, p. 7867 - 7872 (1980)
The electrochemical reduction of diazodiphenylmethane (Ph2CN2) at a platinum cathode in DMF-0.1 F (n-Bu)4ClO4 has been shown to afford benzophenone azine ((Ph2C=N-)2) as the principal product, along with lesser amounts of Ph2CH2 and several other compounds.Product formation occurs by a chain process in which the carbene anion radical, Ph2C-., is produced from electrogenerated Ph2CN2-. by rapid loss of nitrogen.Ph2CH-, the first-observed intermediate in Ph2CN2 electroreduction, is obtained from Ph2C-. either by protonation followed by reduction or by hydrogen atom abstraction from a component of the solvent-electrolyte system.Propagation of the chain involves coupling of Ph2CH- with Ph2CN2 to produce Ph2CHN=CPh2 followed by proton transfer from this anion to Ph2C-. to give (Ph2C=N-)22- and Ph2CH., respectively.Regeneration of Ph2CN2-. occurs by electron transfer from either (Ph2C=N-)22- or (Ph2C=N-)2-. to Ph2CN2.Termination of the chain occurs upon protonation of Ph2CH-.In the presence of the electroinactive proton donors, diethyl malonate and 2,2,2-trifluoroethanol, azine formation is interdicted and Ph2C=NNH2 and Ph2CH2 are the two major products.Studies of the Ph2CH2/Ph2C=NNH2 product ratio as a function of proton donor concentration and temperature have established that protonation (and other reactions) of Ph2CN2-. occurs exclusively on terminal nitrogen while Ph2CH2 arises via Ph2C-..No evidence was obtained for either hydrogen atom abstraction by or protonation of Cα of Ph2CN2-..
Benzylation of benzene by benzyl chloride over silica-supported iron sulfate catalysts
Shuvaeva, Maria A.,Nuzhdin, Alexey L.,Martyanov, Oleg N.,Bukhtiyarova, Galina A.
, p. 231 - 232 (2014)
The silica-supported Fe-containing catalysts prepared using FeSO 4 as a precursor exhibit high activity toward the reaction of benzene with benzyl chloride.
Observation and Modelling of the Recombination Kinetics of Diphenylmethyl Radicals in the Cavities of Na-X Zeolite
Johnston, Linda J.,Scaiano, J. C.,Shi, Ji-Liang,Siebrand, Willem,Zerbetto, Francesco
, p. 10018 - 10024 (1991)
An experimental and theoretical study is reported of the recombination of diphenylmethyl radicals generated from precursors included in Na-X zeolite.These precursors, 1,1,3,3-tetraphenylacetone and 1,1-diphenylacetone, are decomposed by flash photolysis, yielding a radical pair in a triplet configuration.The diphenylmethyl radical concentration, monitored by time-resolved diffuse reflectance spectroscopy, decreases roughly linearly with logarithmic time, indicative of a reaction rate that decreases gradually.The overall decay pattern depends only weakly on temperature, precursor, or laser dose.Product analysis indicates that geminate recombination, which requires a radical pair in a singlet configuration, is the dominant decay mechanism, consistent with the known mobility of diphenylmethyl radicals in the Na-X lattice.This face-centered lattice consists of large cavities each connected by channels to four other cavities situated at the corners of a tetrahedron.To describe the diffusion of the radicals in this lattice, a random walk model is adopted and solved by computer simulation.For short times (200 ns-10 μs) and low precursor concentrations, the rate of geminate recombination generated by the model yields a satisfactory reproduction of the observed time dependence, but for long times the fraction of radicals surviving geminate recombination falls well below the theoretical limit of 51 percent.There is evidence that quenching processes other than nongeminate recombination are responsible for this behavior.It is found that the spin flip required to allow recombination is fast on the time scale of radical hopping and that the hopping rate of the order of 106 - 107 s-1 at room temperature is thermally activated with a substantial activation energy (ca. 2 kcal/mol in the range 244-327 K).
Towards iron-catalysed suzuki biaryl cross-coupling: Unusual reactivity of 2-halobenzyl halides
Bedford, Robin B.,Gallagher, Timothy,Pye, Dominic R.,Savage, William
, p. 1761 - 1765 (2015)
The reaction of 2-halobenzyl halides with the borate anion Li[(Ph)(t-Bu)Bpin] leads not only to the expected arylation at the benzyl position, but also to some Suzuki biaryl cross-coupling. Preliminary mechanistic investigations hint towards the intermediacy of benzyl iron intermediates that can either: (a) directly cross-couple with the aryl boron reagent to give observed monoarylated species, or (b) undergo oxidative addition of the aryl halide to generate the diarylated species on reaction with the boron-based nucleophile.
CONTRASTING CHEMISTRY OF DIPHENYLCARBENE AND FLUORENYLIDENE IN CYCLOHEXANE
Savino, T. G.,Senthilnathan, V. P.,Platz, M. S.
, p. 2167 - 2180 (1986)
The chemistry of diphenylcarbene and fluorenylidene in cyclohexane was investigated.An examination of the product distributions, radical scavening experiments and isotopic fractionation established that diphenylcarbene reacts with cyclohexane predominantly, if not exclusively, through its triplet state whereas fluorenylidene exhibits substantial chemistry from its low lying singlet state in addition to some triplet chemistry.The results indicate that the singlet-triplet splitting of fluorenylidene is smaller than in diphenylcarbene.The chemical studies are in accord with previous laser flash photolysis experiments.
Nickel-Catalyzed Cross-Electrophile Coupling with Organic Reductants in Non-Amide Solvents
Anka-Lufford, Lukiana L.,Huihui, Kierra M. M.,Gower, Nicholas J.,Ackerman, Laura K. G.,Weix, Daniel J.
, p. 11564 - 11567 (2016)
Cross-electrophile coupling of aryl halides with alkyl halides has thus far been primarily conducted with stoichiometric metallic reductants in amide solvents. This report demonstrates that the use of tetrakis(dimethylamino)ethylene (TDAE) as an organic reductant enables the use of non-amide solvents, such as acetonitrile or propylene oxide, for the coupling of benzyl chlorides and alkyl iodides with aryl halides. Furthermore, these conditions work for several electron-poor heterocycles that are easily reduced by manganese. Finally, we demonstrate that TDAE addition can be used as a control element to ‘hold’ a reaction without diminishing yield or catalyst activity.
Novel coupling reaction of pentaarylantimony with carbon electrophiles
Fujiwara, Masahiro,Tanaka, Mutsuo,Baba, Akio,Ando, Hisanori,Souma, Yoshie
, p. 39 - 42 (1996)
The cross-coupling reactions of pentaarylantimony with organic halides and allyl acetate were studied under various conditions of acetonitrile solvent, palladium catalysts and copper iodide. Acetonitrile solvent enabled a nucleophilic coupling reaction with allylic halides, although a radical reaction and an intramolecular ligand coupling have been regarded as general under other conditions. Palladium catalysts were effective for the coupling reaction with allyl acetate. Copper iodide promoted the reaction of organic halides, such as methyl iodide and ethyl bromoacetate. In the latter two cases, the formation of diaryls is a significant side reaction.
Scandium(III) trifluoromethanesulfonate-catalysed reductive Friedel-Crafts benzylation of aromatic compounds using arenecarbaldehydes and propane-1,3-diol
Tsuchimoto, Teruhisa,Hiyama, Tamejiro,Fukuzawa, Shin-Ichi
, p. 2345 - 2346 (1996)
Scandium(III) trifluoromethanesulfonate catalyses the Friedel-Crafts benzylation of aromatic compounds with arenecarbaldehydes and propane-1,3-diol to produce, through a clean redox process, diarylmethanes in high to excellent yields.
Photoinduced Cleavage of the C-C Bonds of 9-Alkyl-10-methyl-9,10-dihydroacridines by Perchloric Acid
Fukuzumi, Shunichi,Tokuda, Yoshihiro,Fujita, Morifumi
, p. 1905 - 1908 (1991)
The C-C single bonds of 9-alkyl-10-methyl-9,10-dihydroacridines are readily cleaved by perchloric acid in acetonitrile under irradiation of the absorption band of AcrHR to yield the corresponding alkane (RH) and 10-methylacridinium ion (AcrH+).
