Oxidation 1,1-diphenylethylene

For some of these reactions detailed mechanistic studies were carried out. As an example, in Scheme 5 the pathway suggested for 1.1-diphenylethylene oxidation with O2 into benzophenon [23] is shown. 

Soveral 1,1-diarylethylcne oxides have been subjected to Ihr action of magnesium bromide or boron trifluoride (Eq. 453). Again, migratory aptitude in the epoxide-isomerization process appears to l -a function of the overall substitution pattern. Thus, 1,1-diphenyi ethylene oxide and 2-methyl-1,1 -diphenylethylene oxide -J suffer hydride shifts exclusively. On the other hand, 2-ethyl-i.i-diphenylethylene oxide reportedly undergoes hydride shift and cthvl migration... 

Tetraphenylethylene oxide—no reaction 1,1-Diphenylethylene oxide—no reaction Burgstahler prepared the reagent by stirring lithium shot in ethylamine until the blue color was completely discharged and used it for isomerization of the non-conjugated diene (1) to (2). Mineral acids failed to effect isomerization. Lithium di-... 

An ethereal soln. of 1,1-diphenylethylene oxide and 98%-H202 stirred several days at room temp. product. Y 92%. F. e. s. W. Adam and A. Rios, Chem. Commun. 1971, 822. 

The oxidative coupling of alkenes which have two substituents at the 2 posi-tion, such as isobutylene, styrene, 2-phenylpropene, 1,1-diphenylethylene, and methyl methacrylate, takes place to give the 1,1,4.4-tetrasubstituted butadienes 285 by the action of Pd(OAc)2 or PdCF in the presence of sodium acetate[255-257]. Oxidation of styrene with Pd(OAc)2 produces 1.4-diphenylbutadiene (285, R = H) as a main product and a- and /3-acetoxystyrenes as minor pro-ducts[258]. Prolonged oxidation of the primary coupling product 285 (R = Me) of 2-phenylpropene with an excess of Pd(OAc)2 leads slowly to p-... 

Scintillation detectors are substances which fluoresce when stmck by x-radiation. Scintillation can, therefore, serve to convert x-ray photons into visible or ultraviolet light. Scintillation materials include thaUium-activatedcrystals of sodium iodide, NaI(Tl), potassium iodide, KI(T1), or cesium iodide, CsI(Tl) crystals of stilbene (a, P-diphenylethylene) [588-59-0] and anthracene [120-12-7] bismuth germanium oxide [12233-56-6] ... 

Diphenylcyclopropenone, 47, 62 Dii henyldiacetylene, 45, 39 Diphenyl disulfide, oxidation to methyl benzenesulfinate, 46, 62 1,1-Diphenylethylene, reaction with N,or diphenylmtrone, 46,129 N,N -Diphi iiyli tiiyleni diamine, condensation with triethyl orthoformate, 47, 14... 

Dimsyl anion 88 is known to add to styrene, and to 1,1-diphenylethylene in the presence of a base, forming 3-arylpropyl methyl sulfoxides121. Treatment of ( )-3,3-dimethyl thiacyclo-oct-4-ene-l-oxide 89 with n-BuLi gave exo-4,4-dimethyl-2-thiacyclo-[3.3.0]octane 2-oxide 90, a bicyclic addition product of the internal double bond. A similar cyclization was observed in the reaction of 91 with n-BuLi122. 

Diphenylcyclopropane has been prepared in 24% yield by the Simmons-Smith reaction,2 in 78% yield by treatment of 3,3-diphenylpropyltrimethylammonium iodide with sodium or potassium amide,3 in 61% yield by reaction of 1,1-diphenyl-ethylene with dimethylsulfonium methylide,4 and in unspecified yields from 1,1-diphenylethylene by reaction with diazomethane followed by pyrolysis of the resulting pyrazoline or by reaction with ethyl diazoacetate followed by distillation of the corresponding acid over calcium oxide.5... 

Diphenylethanal, by oxidation of 1,1-diphenylethylene with chromyl chloride, 51,... 

Particularly, the trans isomer of l,2-dimethyl-l,2-diphenylethylene is coplanar and the cis isomer is noncoplanar. However, both isomers are oriented in an identical manner within the electrode space and electric field (Homer and Roder 1969). The energy needed for such an orientation is not markedly reflected in the value of a potential. For oxidation potentials, there are also data that these potentials are not sensitive to diastereoisomerism (Fukui et al. 2007). 

Diethynylphenol, 3244 2,3-Dimethyl-l,3-butadiene, 2407 6,6-Dimethylfulvene, 2967 1,1-Diphenylethylene, Oxygen, 3642 Formaldehyde oxide polymer, 0419... 

But the same 1, 1-diphenylethylene when reacted in the presence of fluorohectorite gives oxidized products, 1, 1-diphenylethane and benzophenone. 

The second electronic transfer to the oxygen produces the diradical (C) which evolves into monomer formation. The latter possibility (IV) is a homolytlc cleavage giving another anion radical. If the process follows scheme III or IV, we must obtain monomer formation after the oxidation reaction in all cases. We have carried out the oxidation of carbanionic dimers derived from isoprene, crmethylstyrene, styrene, 1,1-diphenylethylene. 

Since the oxidation potential of 1,1-diphenylethylene is +1.8 V in acetonitrile formation of its radical cation should be thermodynamically permissible on... 

The reactivity of a halogen compound in dehydrohalogenation over solid catalysts also depends on its steric arrangement. This was shown by studying the dehydrohalogenation of the rigid molecules l-bromo-1,2-diphenylethylene [188] and l-chloro-l,2-diphenylethylene [171] on catalysts of the type of metal salts and metal oxides the cis-compound was always more reactive than the trans-derivative. 

While the exploration of the implications of irradiated semiconductor surfaces for organic chemistry have only recently been attempted, there now exists a growing body of experiments illustrative of their power (283). A typical example of the contrasting oxidative reactivity observed on irradiated semiconductor surfaces can be seen in the different product distributions obtained by oxidation of 1,1-diphenylethylene photo-electrochemically on Ti02, electrochemically on Pt (an inert electrode material), and with thermal single electron transfer catalysts in homogeneous solution, eq. 89 (284) ... 

In view of the above results, in photocatalytic oxidation of a series of 4-substituted diphenylethylenes, an increase in reactivity with decreasing Hammett s sigma constants (31) seems to arise not only from the lowering of the oxidation potentials of the olefins in this sequence but also from the general trend of the increase in the reactivity of olefins toward peroxyl radicals with increasing the electron donating ability of olefins (33). 

Anodic oxidation of tetraphenylethylene at a platinum electrode leads to the product of cyclization, namely, to 9,10-diphenylphenanthrene (Stuart Ohnesorge 1971). The intramolecular coupling reaction does not occur when diphenylethylenes, i.e., stilbene and its methyl derivatives, are electrolyzed under the same conditions (Stuart Ohnesorge 1971). This difference in the anodic behavior of these substances was attributed to the low stability of the cation radicals of stilbene and its methyl derivatives in comparison to the cation radicals of tetraphenylethylene. The participation of the cation radicals in cyclization of tetraphenylethylene has been unequivocally proved (Svanholm et al. 1974 Steckhan 1977). 

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