Diphenyl compounds

Dissolve 12 g. of aniline hydrochloride and 6 g. of urea in 50 ml. of warm water, and then filter the solution through a fluted filter to remove any suspended impurities which may have been introduced with the aniline hydrochloride. Transfer the clear filtrate to a 200 ml. conical flask, fit the latter with a reflux water-condenser, and boil the solution gently over a gauze for about hours. Crystals of diphenylurea usually start to separate after about 30-40 minutes boiling. Occasionally however, the solution becomes supersaturated with the diphenylurea and therefore remains clear in this case, if the solution is vigorously shaken after about 40 minutes heating, a sudden separation of the crystalline diphenyl compound will usually occur. The further deposition of the crystals during the re-... 

As already indicated, the polycarbonates may be produced from a wide range of polyfunctional hydroxy compounds. In practice only the diphenyl compounds have proved of much interest and the only polycarbonate of commercial significance is derived from bis-phenol A 2,2-bis-(4-hydroxyphenyl) propane. 

Polycarbonates have also been prepared from diphenyl compounds where the benzene rings are separated by more than one carbon atom. In the absence of bulky side groups such polymer molecules are more flexible and crystallise very rapidly. As is to be expected, the more the separating carbon atoms the lower the melting range. This effect is shown in data supplied by Sehnell" Table 20.11). 

Diphenyl compound (i.e. linkage bet >een rings) Melting range of polymer (°C) Solubility of polymer in ordinary solvents... 

Diphenyl Compound of a Group 12 Element, the Case of HgPh2. 193... 

A large number of stable planar, tetrahedral, or octahedral complexes of lb, lib, and Vlllb elements (Cu2+, Zn2+, Co2+, Ni2+, Ru2+, Rh2+, Pd2+, Pt2+, Pt4+) using cyclopropenones (preferentially the diphenyl compound) as ligands has been evaluated mainly by Bird281. Their preparation may start either with metal salts or with carbonyls, as the octahedral Co(II) complex [Co(Dcp)6]2+ may exemplify ... 

Poly(ketone)s obtained from 2,2-bis(4-carboxyphenyl)-l 1,1,3,3,3-hexa-fluoro-propane 15 with diphenyl compounds dissolve readily in aprotic polar... 

The reaction of various A-tosylated a-amino acids (94) with benzene in concentrated sulfuric acid yielded diphenyl derivatives (95)." The mechanism proposed for the reaction (Scheme 9) involves initial protonation of the carboxyl group to give (96), which suffers decarbonylation to the A-tosyliminium salt (97). This reactive electrophile (97) interacts with benzene to give a monophenyl compound (98) which, via a Friedel-Crafts reaction, interacts with another molecule of benzene to yield the diphenyl compound (95)." Toluene and p-xylene reacted analogously to yield diarylated products. 

Imidazoles unsubstituted at the 4- and 5-positions give polychloro-2f/-imidazoles with chlorine. In contrast, the 4,5-diphenyl compounds 40 (R = H, Me, Ph) yield 4f/-imidazoles 41, in which = Cl, CCI3, and Ph, respectively (Scheme... 

Reaction of the 2-acetoxy-3(2//)-furanones (526) with monosubstituted hydrazines gives good yields of the pyridazinium-5-olates (527) together with varying amounts of isomeric products. Alkyl derivatives (527 R = alkyl) have also been prepared by base-catalyzed alkylation (Mel, Me2SO4, PhCH2Cl) of 3-methyl-6-phenyl-5-ethoxycarbonyl-4( 1 //)-pyridazinone. Reduction of the diphenyl compound 527 (R = Ar = Ph) by zinc and hydrochloric acid gives 3-ethoxycarbonyl-5-hydroxy-5-methyl-l,2-diphenyl-2-pyrrolin-4-one (528 R = Ar = Ph) (Scheme 21... 

Remarkably, the stability of the molecular ion associated with the furan and benzofuran nuclei is preserved into the benzo[c]furan series. For the 1,3-diphenyl compound the fragmentation path is believed to be as shown in Scheme 12, the molecular ion being by far the most abundant (760MS258). 

Compounds (11) were also prepared in low yield by oxidation of the bishydrazine (20) by sodium hypochlorite (72JA8497), potassium ferricyanide or potassium permanganate (Scheme 3) (73CB3097). The l,4-dibenzyl-5,6-diphenyl compound (22) was prepared from 1,1,4,4-tetrabenzyltetrazene (21) by oxidative cyclization using thionyl chloride (73CL51). 

Reaction LII. (b) Action of Cuprous Chloride on Nitro-diazonium Compounds. (B., 34, 3802 38, 725.)—Ordinarily when cuprous chloride acts on a diazonium salt in acid solution, a chloro-compound is the chief product (Sandmeyer s reaction, p. 345), and only a small quantity of the corresponding diphenyl compound is formed. But if a nitro-diazonium... 

Oxazoles with a free 2-position are metallated thereat by n-butyllithium, while 2,4,5-trimethyloxazole forms the anion (142) (81JOC1410). In the presence of a carboxyl or methoxycarbonyl group at C(4) the metallation is directed to the 5-position, even in the absence of a 2-substituent, to give, for example, the lithio compounds (143) and (144) (81TL3163). 2-Lithiooxazoles can equilibrate with open-chain isocyanides and the diphenyl compound has been trapped as a mixture of cis- and /rans-trimethylsilyl ethers (equation 9). 

The following diphenyl compounds require refluxing chloroform for formation1 cyano(methoxycarbonyl)methylidene diphenyl tellurium yield 78% oil... 

In contrast to benzyl alcohol, a-substituted benzyl alcohols, benzyl ethers, and aryl ketones may be successfully hydrogenated over rhodium and rhodium-platinum catalysts to give the corresponding saturated products in high yields, as shown in eqs. 11.38-11.41. In the hydrogenations shown in eqs. 11.38 and 11.39, no racemization took place D-mandelic acid afforded D-hexahydromandelic acid in 94% yield and meso- and dl-2,3-dicyclohexyl-2,3-butanediol were obtained in 93 and 94% yields, respectively, by hydrogenation of the corresponding diphenyl compounds. 

Of the commercially-available phenylene diamines tested, the N,N -diphenyl compound is an insoluble, high melting-point, crystalline solid, whereas the unsymmetrically substituted N-phenyl-N -(2-octyl) derivative is a liquid, readily miscible... 

Effluents from the alkylation and transalkylation reactors are fed to the benzene column (3), where unreacted benzene is recovered from crude EB. The fresh benzene feedstock and a small vent stream from the benzene column are fed to the lights column (4) to reject light impurities. The lights column bottoms is returned to the benzene column. The bottoms from the benzene column is fed to the EB column (5) to recover EB product. The bottoms from the EB column is fed to the PEB column (6) where recyclable alkylbenzenes are recovered as a distillate and diphenyl compounds are rejected in a bottoms stream that can be used as fuel. 

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