40673-57-2Relevant articles and documents
Synthesis of Dibenzyls by Nickel-Catalyzed Homocoupling of Benzyl Alcohols
Pan, Feng-Feng,Guo, Peng,Huang, Xiaochuang,Shu, Xing-Zhong
, p. 3094 - 3100 (2021/04/23)
Dibenzyls are essential building blocks that are widely used in organic synthesis, and they are typically prepared by the homocoupling of halides, organometallics, and ethers. Herein, we report an approach to this class of compounds using alcohols, which are more stable and readily available. The reaction proceeds via nickel-catalyzed and dimethyl oxalate assisted dynamic kinetic homocoupling of benzyl alcohols. Both primary and secondary alcohols are tolerated.
Generation and Reactivity Studies of Diarylmethyl Radical Pairs in Crystalline Tetraarylacetones via Laser Flash Photolysis Using Nanocrystalline Suspensions
Park, Jin H.,Hughs, Melissa,Chung, Tim S.,Ayitou, A. Jean-Luc,Breslin, Vanessa M.,Garcia-Garibay, Miguel A.
supporting information, p. 13312 - 13317 (2017/10/05)
The nanosecond electronic spectra and kinetics of the radical pairs from various crystalline tetraarylacetones were obtained using transmission laser flash photolysis methods by taking advantage of aqueous nanocrystalline suspensions in the presence of su
Palladium-catalyzed reaction of 2-hydroxy-2-methylpropiophenone with aryl bromides: A unique multiple arylation via successive C-C and C-H bond cleavages
Wakui, Hiroyuki,Kawasaki, Satoshi,Satoh, Tetsuya,Miura, Masahiro,Nomura, Masakatsu
, p. 8658 - 8659 (2007/10/03)
2-Hydroxy-2-methylpropiophenone undergoes a unique multiple arylation via C-C and C-H bond cleavages upon treatment with excess aryl bromides in the presence of a palladium catalyst to give 1,1,2,2-tetraarylethanes and 4,4-diaryl-1-phenylisochroman-3-ones. Copyright
Ytterbium Metal Mediated Desulfurization and Coupling Reaction of Diaryl Thioketones
Makioka, Yoshikazu,Uebori, Shin-ya,Tsuno, Masumi,Taniguchi, Yuki,Takaki, Ken,Fujiwara, Yuzo
, p. 611 - 614 (2007/10/02)
Diaryl thioketones are selectively reduced with ytterbium metal to diarylmethanethiols, diarylmethanes or tetraarylethylenes, via thiometallacycle intermediates which undergo electrophilic coupling at thiocarbonyl carbon and sulfur.
Radical ions in photochemistry. Carbon-carbon bond cleavage of radical cations in solution: Theory and application
Popielarz,Arnold
, p. 3068 - 3082 (2007/10/02)
The cleavage of radical cations of two series of alkanes, 1,1,2-triaryl- and 1,1,2,2-tetraarylalkanes, generated by photoinduced single electron transfer in acetonitrile-methanol, occurs with formation of radical and carbocation fragments. The radical cations of some unsymmetrically substituted alkanes cleave to give all four of the possible products, two hydrocarbons emanating from the radicals and two methyl ethers from the carbocations, in proportion to the oxidation potentials of the two possible radical fragments. There is an excellent linear correlation between the logarithm of the observed ratio of products and that calculated from the reported electrochemically determined oxidation potentials (r = 0.998, 5 points). The proportionality constant (1.27) for this relationship is close to unity which indicates that the product ratio is determined by the relative rates of cleavage in the two possible modes or by equilibration of the radicals and carbocations before separation of the geminate radical carbocation pair and not by equilibration upon reencounter of freely solvated radical and carbocation fragments. The effect of temperature on the relative oxidation potentials of the radicals studied is small and can be neglected when radicals of the same order (i.e., both secondary or both tertiary) and of similar size are compared. The ratio of products obtained upon cleavage of the radical cation at 25 °C can be used to determined standard oxidation potentials of radicals. The oxidation potential of the diphenylmethyl radical (0.350 V vs SCE) has been accepted as the primary standard and the (4-methyl-phenyl)phenylmethyl (0.265 V) and bis(4-methylphenyl)methyl (0.188 V) radicals are established as secondary standards against which the oxidation potentials of other radicals can be measured. Oxidation potentials of several 4-substituted cumyl radicals have been determined by this photochemical method. There is a good (r = 0.987, 5 points) linear correlation between the measured oxidation potentials and the σ+ substituent constants. The reaction constant is appropriately negative and large (p = -6).
Transformation of Carbinols by RuCl2(PPh3)3 and by Some Other Transition-Metal Catalysts
Pri-Bar, Ilan,Buchman, Ouri,Schumann, Hebert,Kroth, Heinz J.,Blum, Jochanan
, p. 4418 - 4428 (2007/10/02)
Several platinoid metal catalysts have been shown to promote reductive coupling, dehydration, disproportionation, and dehydrogenation of diarylcarbinols.Mechanistic studies were performed at 180-210 deg C with benzhydrol as substrate and RuCl2(PPh3)3 as catalyst.In aromatic hydrocarbon solvents the main process is reductive coupling.In this medium solvated RuCl2(PPh3)2 is suggested to be the active catalyst.In dimethyl sulfoxide the starting complex is transformed initially into RuCl2(PPh3)(Me2SO)2 and causes chiefly carbinol dehydrogenation.Ruthenium alkoxides are implied as common reaction intermediates in all four catalyses.Ruthenium hydrides are suggested to take part in the reductive coupling, disproportionation, and dehydrogenation processes.Some aliphatic and primary aromatic alcohols that do not react by themselves in the presence of RuCl2(PPh3)3 can both serve as active hydrogen donors and form crossover products in the presence of secondary and tertiary aromatic carbinols.
