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Upstream product

• 781-33-9 2-methyl-1,1-diphenylpropene 
• 37951-09-0 2-methyl-1,1-diphenyl-propan-1-ol 
• 3677-76-7 2-methyl-1,1-diphenyl-propan-2-ol 
• 611-70-1 phenyl isopropyl ketone 
• 100-58-3 phenylmagnesium bromide 

Downstream Products

• 3677-76-7 2-methyl-1,1-diphenyl-propan-2-ol 
• 101-81-5 Diphenylmethane 
• 29291-01-8 1,1-diphenyl-2-methyl-2-propen-1-ol 
• 37951-09-0 2-methyl-1,1-diphenyl-propan-1-ol 
• 2575-20-4 3,3-diphenylbutan-2-one 
• 3661-63-0 1-methyl-2-phenyl-1H-indene 
• 13740-70-0 2-methyl-1,2-diphenyl-propan-1-one 
• 781-33-9 2-methyl-1,1-diphenylpropene 

Relevant academic research and scientific papers

Catalytic Functionalization of Styrenyl Epoxides via 2-Nickela(II)oxetanes

Low-valent nickel is shown to preferentially isomerize mono- or disubstituted epoxides into their corresponding aldehydes. Experiments with tetrasubstituted epoxides demonstrate that these reactions proceed via reactive 2-nickelaoxetane intermediates, and

Heteropolytungstic acids incorporated in an ordered mesoporous zirconia framework as efficient oxidation catalysts

Ordered mesoporous composite catalysts consisting of nanocrystalline tetragonal ZrO2 and heteropolytungstic clusters, i.e. 12-phosphotungstic (PTA) and 12-silicotungstic (STA) acids, were prepared via a surfactant-assisted co-polymerization route. According to the X-ray diffraction, transmission electron microscopy and N2 physisorption measurements, the resultant materials possess a well-defined mesoscopic order ranging from wormhole to hexagonal pore structure and exhibit large internal surface area (126-229 m2 g-1) and quite narrow pore size distribution (ca. 2.2-2.6 nm in diameter). Energy dispersive X-ray microanalysis and infrared spectroscopy confirms that the heteropoly clusters are well dispersed within the zirconia matrix, while preserving intact their Keggin structure. The inclusion of PTA and STA clusters in the mesoporous framework has a beneficial effect on the catalytic activity of these materials. Although zirconium oxide and heteropoly acids alone show little catalytic activity, the ZrO 2-PTA and ZrO2-STA heterostructures exhibit surprisingly high activity in hydrogen peroxide mediated oxidation of 1,1-diphenyl-2- methylpropene under mild conditions. Indeed, the mesoporous ZrO2-STA composite sample loaded with 5 wt% STA shows a conversion rate that is 17 times higher than the mesoporous ZrO2. The catalytic activity of these materials is related to the spatial distribution of heteropoly acids in zirconia matrix and possible synergistic interactions between the incorporated Keggin units and Zr(iv) oxohydroxide species.

An alternative reaction outcome in the gold-catalyzed rearrangement of 1-alkynyloxiranes

The gold(III)-catalyzed rearrangement of tetrasubstituted 1-alkynyloxiranes is described. This transformation led to a different reaction outcome with respect to related substrates previously studied. Thus, tertiary α-alkynylketones or alkynols can be selectively obtained. Moreover, gold(III) proved capable to catalyze the rearrangement of simple epoxides. These results indicate that gold(III) complexes act as oxophilic Lewis acids rather than π-acids in these transformations.

Oxidative double bond cleavage of α-substituted styrenes with molecular oxygen

Oxidative cleavage of the carbon-carbon double bond of α-substituted styrene derivatives proceeds under an atmospheric pressure of molecular oxygen at the solventless conditions to afford the corresponding ketones in moderate yields with no requirement for transition metal catalysts or photo-activation.

Reactivity and Selectivity in the Oxidation of Styrene Derivatives. IV. Studies on the Oxidation of Substituted β,β-Dimethylstyrenes

The liquid phase oxidation of substituted (p-MeO-, p-Cl-, m-CF3-) 2-aryl-3-methyl-but-2-enes, of 1,1-diphenyl-2-methyl-propene, of 1-ethoxy-2-methyl-1-phenyl-propene and of 9-isopropylidene-fluorene with pure oxygen was investigated in chlorobenzene solution and in presence of cumene and of cumene hydroperoxide in the temperature range 65-125°C. The product yields were determined gaschromatographically. The differences of the activation energies of epoxide formation and the parallel reactions were calculated. They amount to 19-48 kJ/mol. The epoxide selectivity increases with increasing temperature and increasing concentration of olefin. The relative chain propagation constants (kpC=C) were determined by competitive oxidation with cumene. The kpC=C values of substituted β,β-dimethylstyrenes can be correlated by a LFE-relationship with the ionisation energies of the olefins.

Structural Effects of Olefins in the Photooxygenation with Electron-Accepting Sensitizers. Kinetic Approach to Reactive Intermediates

Pulsed laser excitation studies on the reactive species in 9-cyanoanthracene(CNA)-sensitized oxygenation of 1,1-diphenyl-2-methylpropene (1a) and (E)-2,3-diphenyl-2-butene (1b) show that the reaction course is mostly governed by competitive quenching of the CNA excited singlet by 1 and oxygen to produce 1+. and 1O2, respectively.The results indicate that the reaction courses of tetraphenylethylene and 2,3-dimethyl-2-butene, for example, can be explaind by exclusive quenching of sensitizer singlets by the olefin and oxygen, respectively.

Chromyl Complexes in the Direct Epoxidation of Alkenes

Alkenes such as (E)- and (Z)-β-methylstyrene are converted stereospecifically by dinitratodioxochromium(VI), or chromyl nitrate, to the corresponding epoxide with high selectivities in aprotic media under rather mild conditions.The presence of the cosolvents, N,N-dimethylformamide (DMF), acetone, pyridine, etc., is critical for effective epoxidation with this reagent.In DMF and pyridine, the epoxide remains generally intact but in acetone it is transformed to the corresponding alkene ketal which can also be isolated in high yields.The rates of oxidation are evaluated by the competition method, and the relative reactivities of various alkenes toward chromyl nitrate are found to generally parallel those previously determined for other chromyl reagents such as chromic acid, chromyl acetate, and chromyl chloride.Under optimum conditions for epoxidation, chromyl nitrate effects exclusive oxidation of 1,2-diphenylethanol to deoxybenzoin, which is uncontaminated by the usual cleavage products benzaldehyde and benzyl alcohol.Since the latter is known to derive from chromium(IV) intermediates, we conclude that the active species in chromyl epoxidation is oxochromium(V) formed in situ by the prior one-electron oxidation of solvent.The latter is in accord with the efficient transfer of the oxygen atom from macrocyclic oxochromium(V) species previously observed by Grovers and co-workers.The ESR spectra of the transient chromium(V) intermediates derived from chromyl nitrate and chromyl acetate by reduction with cosolvent are reported.

Mechanism of Photoepoxidation of Olefins with α-Diketones and Oxygen

The benzil- and biacetyl-sensitized photoepoxidation of olefins in the presence of oxygen has been studied.The photolytic loss of diketone is not affected by the presence of olefins; the ratio of epoxide formation to diketone consumption is in the range of 1-3.An (18)O-tracer study shows that the epoxide oxygen derives from molecular oxygen and that the recovered oxygen does not scramble.The photoepoxidation is accompanied by C-C bond cleavage; the ratio of epoxidation to C-C scission is not affected by solvent polarity and only slightly affected by the presence of diazabicyclooctane (Dabco).These results are explained by a mechanism involving the addition of oxygen to triplet diketone to give an acylperoxy radical, which is a key epoxidizing species.

The Efficiency of Benzil-Sensitized Photoepoxidation: A Correction

Photosensitized epoxidation of norbornene by benzil leads to about two epoxide molecules or less per diketone molecule consumed, not the larger numbers previously reported.It is not necessary to postulate a chain mechanism for this epoxidation, although side reactions still complicate the process in many cases.

Photoepoxidation of Olefins with Benzoins and Oxygen. Epoxidation with Acylperoxy Radical

Benzoin was photooxidized to yield benzaldehyde, peroxybenzoic acid, and hydrogen peroxide.The addition of styrenes to this photooxidation system afforded high yields of epoxides together with some C-C cleaved products.While the C-C cleavage products increased with increasing concentration of olefins, the epoxide yield was constant and nearly quantitative; the stoichiometry at the infinite olefin concentration was such that 1 mol of benzoin produces 1 mol of epoxide and 2 equiv of C-C cleaved product.The effect of olefin concentration is analyzed to show that the C-C cleavage is ascribed to benzoyloxy and α-hydroperoxy radicals, PhCH(OH)OO..The photoepoxidation proceeds by a way of acylperoxy radical, affording predominantly trans-epoxide (e.g., 100percent trans-epoxide from stilbenes and 77percent trans-epoxide from 2-octenes).The relative reactivities of olefins differ significantly from those with molecular peroxyacid; the additivity of methyl substitution does not hold, and aliphatic olefins are less reactive than the corresponding aromatic ones.The relative reactivities of photoepoxidation are examined on the basis of the stability of a resulting adduct radical between the acylperoxy radical and olefin.The peroxy radical is not reactive toward pyridine or sulfoxides.The photoepoxidation with benzoin ethers proceeds similarly except the formation of esters, which is explained by the β-scission or the 1,2-phenyl migration of intermediary α-alkoxy radical.These results are discussed in relation to practical photopolymerizations and to an origin of photoxic substances.