Diaryl ethanals

An increase in the electronegativity of R is expected to result in a decreased rate of carbonium ion formation, a relationship shown to hold for substituted 1 l-diaryl-ethanes (84),... 

The dimerization of toluene and substituted toluenes leads to diaryl-ethanes 2S.28.32) Electron-attracting substituents favour the reaction 32) while electron-donating groups reduce the yield. In alkylaromats with straight or branched alkyl groups it is almost always the weakest bond of the side chain which is broken 25 >28>. The resulting radicals combine to diarylethanes or substituted diarylethanes ... 

Nickel(O) triphenylphosphine species have been used to convert allyl halides to 1,5-hexadiene [332], for the reductive coupling of ethylene with aryl halides to give 1,1-diaryl-ethanes [333], and for the coupling of aryl halides and alkenes to prepare substituted olefins [334], In addition, l,2-bis[(di-2-propylphosphino)benzene]nickel(0) has been used for the reductive coupling of aryl halides [335], and l,2-bis[(diphenylphosphino)ethane]-nickel(O) has been employed to synthesize biphenyl from bromobenzene [336] and to prepare benzoic acid from bromobenzene in the presence of carbon dioxide [337]. 

Terminal diarylation[41 synthesis of A,./V-dimethyl-2-[2,2-diarylethenyloxy] ethanamine with subsequent hydrolysis furnishing diaryl ethanals... 

TERMINAL DIARYLATION[4] SYNTHESIS OF N,N-DIMETHYL-2-[2,2-DIARYLETHENYLOXY]ETHANAMINE (6) WITH SUBSEQUENT HYDROLYSIS FURNISHING DIARYL ETHANALS (7) (TABLE 5.2)... 

Preferred gauche conformations of 1-alkyl-2-arylethanes and 1,2-diaryl-ethanes have been interpreted in terms of attractive steric interactions between the hydrocarbon moieties (Hirola et al., 1985), and, by having opposite polarity in the aryl groups, electrostatic or charge-transfer interactions may stabilize the gauche form of 1,2-diarylethanes (El-Torki and Jacobus, 1985). 

The condensation of aromatic rings with aldehydes or ketones is called hydroxy-alkylation. The reaction can be used to prepare alcohols, though more often the alcohol initially produced reacts with another molecule of aromatic compound (11-12) to give diarylation. For this the reaction is quite useful, an example being the preparation of l,l,l-trichloro-2, 2-bis (p-Chlorophenyl) ethane (DDT) ... 

This procedure is especially suited for preparing variously substituted diarylmethanes.1 6 The l,l-diaryl-2,2,2-trichloro-ethanes may be converted to the corresponding benzophenones via the l,l-diaryl-2,2-dichloroethylenes7 and to 1,1 -diarylacetic acids.8... 

DR. GEOFFROY Let me answer the last question first. I don t fully understand cis-methyl groups. When complexes containing those have been irradiated, one generally doesn t observe the formation of ethane. Instead, where the chemistry is well-defined, it looks as if solvolysis simply occurs to yield radicals. There are, however, some cases of diaryl complexes which, when irradiated, will couple two phenyl ligands to give biphenyl as a product. 

The palladium-phosphine-catalyzed cycloaddition reactions of vinyloxetanes 530 with aryl isocyanates or diaryl-carbodiimides led to 4-vinyl-l,3-oxazin-2-ones 531 or l,3-oxazin-2-imines 532, respectively (Scheme 101). In the absence of phosphine ligands (PPhs, bis(diphenylphosphino)ethane (DPPE), l,3-bis(diphenylphosphino)propane (dppp), no conversion of heterocumulenes was observed. Starting from fused-bicyclic vinyloxetanes, both types of cycloadditions proceeded in a highly stereoselective fashion, affording only the r-isomers of alicycle-condensed 1,3-oxazine derivatives <1999JOC4152>. 

CA 53, 17513 (1959). Materials useful as rocket fuels, semisolid or gelled fuels for bursting and tail-ejection-type bombs, and incendiary fuels for flame throwers and hand grenades are described. They are made by mixing 0.1-25% by wt of satd, unsatd, or aromatic nitrohydrocarbons or their mixts, such as nitro- or dinitromethane, -ethane, -propane, or -butane with divinylated ketoses or diaryl deoxyketitols prepd by reaction of C3 g ketose sugars with C6 M aromatic hydrocarbons. The latter include CfiH, toluene, naphthalene, anthracene and their alkylated derivs... 

The reaction of 1 -benzyl- 1,4-dihydronicotinamide (BNAH) with a series of 1,1-di-para-substituted-phenyl-2,2-dinitroethylenes in oxygen-saturated acetonitrile produced various amounts of the corresponding ethanes and diaryl ketones depending on the electronic structure of the substituent groups, thereby indicating a spectrum of behaviour intermediate between polar and SET mechanisms (Scheme ll).261... 

Diaryl- -(tu-hydroxy-ethylester) E2, 210 1-Diazo-alkan- -ester E2, 398 (l-Diazo-ethan)-phenyl- -methylester E2, 399 (Diazo-phenvl-methan)-phenyl- -methylester E2,... 

Dihaloethanes alkylate arenes under Friedel-Crafls catalysis by Lewis acids to afford 1,2-diaryl-ated ethanes. Dolgov and Larinsuggested that the reaction process via the intermediate monoaryI-ated haloethane (Scheme 11) which affords the final product via a phenonium-type intermediate. 

Amino-4-brom-5(3)-phenyl-1H-pyrazol kondensiert mit 1,2-Diaryl-2-hydroxy-l-oxo-ethan beim Er-hitzen in Ethanol z. B.2039 ... 

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