Diphenyl methanes, synthesis

When pure phenylacetaldehyde was treated under the conditions that resulted in the conversion of benzyl alcohol to toluene and 2-phenyl-ethanol, the phenylacetaldehyde polymerized and no identifiable reaction products were secured. More information on this matter was obtained with the substituted benzyl alcohol, benzhydrol. Benzhydrol, on treatment with synthesis gas, gives an almost quantitative yield of diphenyl-methane. The hydrocarbon may be formed by decarbonylation of the intermediate diphenylacetaldehyde, or by direct hydrogenolysis of the alcohol ... 

Diphenyl-methane, Methylene-diphenyl, Ditane or Benzylbenzene, CgHj-CHg-CgHB mw 168.23 col crysts, sp gr 1.001 at 26/4°, mp 26.6°, bp 265° insol in w v sol in ale in eth. It can be prepd by condensation of benzylchloride with benzene in presence of A1 chloride. Used in organic synthesis (Refs 1 10)... 

The Friedel and Crafts synthesis is of particular value in the preparation of certain classes of hydrocarbons. Diphenyl-methane is best prepared in this way from benzylchloride, C6H5CH2CI —... 

This synthesis, in common with the production of anthracene based on diphenyl-methane by Friedel-Crafts reaction and dehydrogenation, has had no industrial significance to date. 

Fig. 4. Synthesis of monodisperse a-hydro-co-hydroxypoly-(oxytetramethylene) (POTM-n) and their diphenyl-methane- 4 -carbamate derivatives (POTM-n-Urethane)...

V, Cr, and Mn ions were the most active. V-MCM-41 catalyst, with a better structural pattern, showed a better conversion in the oxidation of ethyl benzene and diphenyl methane than Ti- and Cr-MCM-41 catalysts [80]. The catalytic activity of MCM-41 modified with V, Co, Nb, and La was evidenced in the oxidation with H2O2 of alcohok (hexanol, cyclohexanol, and hexanediol) and aromatic hydrocarbons (styrene, benzene, and toluene). The effect of synthesis method on catalytic properties was evidenced for all of them [35,79]. 

A 10-20%-soln. of the startg. m. (mixture of cis- and rrawj-isomers) in diphenyl-methane heated at 280-300° in a Pyrex ampoule methyl 3-methyl-2-butenoate. Y 90%.-In combination with photochemical oxetane ring synthesis from ethylene derivs. and oxo compds. (s. Synth. Meth. 19, 764), ethylene deriv.-oxo compd. interconversion may be achieved. F. e. s. G. Jones II, S. B. Schwartz, and M. T. Marton, Chem. Commun. 1973, 374. 

One of the driving forces behind recent developments in the synthesis and characterization of new acids is the requirement to replace mineral acids by reagents and catalysts that will lead to reduction in waste, in other words to an improved atom economy. Thus, HCl used in the synthesis of diamino diphenyl methane, an intermediate in polyurethane production, can be replaced by a silico-aluminate catalyst in which the acid sites of the zeolite are accessible through the external surface. Less conventionally, simple aromatic hydrocarbons can be nitrated using 60-70% nitric acid in the presence of the strong Lewis acids, lanthanide-perfluoroalkane sulfonic acid salts, such as the ytterbium(lll) compounds (VI) and... 

Scheme 33a Synthesis of N,N -Tetraglycidyloxyl diamino diphenyl methane (TGDDM).

Applied to the synthesis of hydrocarbons the following results have been obtained by this new method. 9 10-Diphenyl-9 10-dihydroanthracene is formed by the condensation of benzene and chloroform, whilst in the ordinary Friedel-Crafts reaction (A., 194, 254 227, 107) triphenyl-methane (Preparation 6) is the main product, traces of chlorarylmethanes and tetraphenylethane (B., 26, 1952) being also formed. The same compound is also obtained from benzal chloride and benzene. Carbon tetrachloride and benzene give 9 9 10 10-tetraphenyl-9 10-dihydroanthracene as do also phenylchloroform and benzene. In the older reaction triphenylchloromethane (p. 432) is the chief product. 

The synthesis of cobalt meso-diphenyl corrolates has also been reported [31]. The synthetic procedure involves the acidic condensation of 3,4-dimethyl-2-(a-hydroxybenzyl)pyrrole-5-carboxylic acid with 3,3, 4,4 -tetramethyl dipyrro-methane, followed by reaction with cobalt salts. The reaction afforded a mixture of two isomers Co(5,15-OMDPC)PPh3 and Co(5,10-OMDPC)PPh3. The formation of this latter isomer has been explained by the high tendency of self condensation of the starting pyrrole under the reaction conditions, 2-(a-hydroxybenzyl)meso-phenyl dipyrromethane can be formed. This species would afford the Co(5,10-OMDPC)PPh3 by further condensation with the dipyrromethane unit present in excess in the reaction mixture. 

Mitsunobu reaction has also found use for the synthesis of nucleoside analogues. The reactions of diphosphines with cyanamide or sulphamide in the presence of diethyl azodicarboxyl ate have given bis-azenes, e.g.,(76). In a similar manner tris-X -azenes have been obtained from triphosphines Bis(diphenyl-phosphino)methane reacts cleanly with trimethylsilylazide to give, initially, one isomeric form of the silylated monophosphazene (77)... 

There is another synthesis of organosilicon halides, not generally applicable, but important in industry because the starting materials are cheap this is the treatment of silicon halides with hydrocarbons at high temperatures. As examples, tetrachlorosilane and benzene in the gas phase at 840° give dichloro(diphenyl)silane 372 tetrachlorosilane and methane in the gas phase give trichloro(methyl)silane at 960° in the presence of an iron catalyst372 and at 500° in the presence of a brick or pumice catalyst.373... 

The reaction of phosphorous esters and amides with polyhalogeno-methanes has been studied and used in a synthesis of phosphates. The reaction of diphenyl phosphorochloridate (103), produced in situ from diphenyl phosphonate and carbon tetrachloride, has been studied with various diamines. ... 

Diphenylmethane, (C6H5)2CH2, is best prepared from benzyl chloride, C6H5CH2CI, and benzene by the Friedel and Crafts synthesis. It melts at 26° and boils at 262°. Homo-logues of this compound can be prepared from aldehydes and aromatic hydrocarbons by the action of sulphuric acid. Thus, aldehyde or acetal and benzene when shaken with sulphuric acid give diphenyl-methyl-methane (unsymmetrical diphenylethane) ... 

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