Ethane Friedel-Crafts reaction

Friedel-Crafts reaction with aluminum chloride in sym-tetrachloro-ethane gave 7-keto-4-methoxyhomoperinaphthane (XCIII) in 41% yield. Heating the free acid with stannic chloride, however, produced l-keto-8-methoxy-l,2,3,4-tetrahydrophenanthrene (XCY) in 40% yield... 

Di-benzyl is therefore symmetrical di-phenyl ethane as is also proven by its preparation from symmetrical di-chlor ethane, by the Friedel-Craft reaction, with benzene as follows ... 

Friedel and Crafts (who later became the president of MIT) discovered this reaction in 1879, but seven years before, Baeyer and his colleagues carried out very similar reactions using aldehydes as the alkylating agent and strong acids as catalysts. These reactions, like the Friedel-Crafts reaction, proceed through carbocation intermediates. Consider the synthesis of DDT (l,l,l-trichloro-2,2-di(p-chlorophenyl)ethane)) ... 

Bis(3,4-dicarboxybenzoyl)phthalocyanines with M = Co(II) or Cu(II) have been covalently bound to linear polystyrene by a Friedel-Crafts reaction [130], The polymers contained 0.13 mmol g (12.4 wt.%) phthalocyanine moieties. The sensitivity of the polymers toward toxic gases were investigated by quartz balance transducers. The sensitivities are 6T0" m mL for NO2 and 2T0 m mL for chloroform and perchloroethylene, respectively. 52 (R = SO2CI, M = Fe) has been covalently bound to the amino groups of a cross-linked, hydrophilic polymer consisting of A/ -acryloyl-P-alanine-(aminoethyl-ene)-amide, A -acryloylpyrrolidine and 7V,A -bis(methacryloyl)-l,2-diamino-ethane as comonomers [131]. The polymer obtained, 52, contains 20 pmol phthalocyanine units per g. The catalytic oxidation of 2,4,6-trichlorophenol or 3,5-di-tert-butylcatechol in the presence of H2O2 or KHSO5 as oxidant has been studied. Around 80% of the trichlorophenol was catalytically oxidized within 2 h at pH 7. 

An unusual Friedel-Crafts reaction occurs between pentafluorobenzene and hexafluoropropene in the presence of antimony pentafluoride cis- and rranj-perfluoro(propenylbenzene), C,F6 CF CF CF3, and /rons-perfluoro-(1,3-diphenylpropene), CeF5-CF CF CF, C,Fs, are formed, probably via the carbocations (CF2i CFiiiCF, + and (C,Fs-CF CF--iiCF3)+. The reaction between pentafluorobenzene and 1,1,2-trichlorotrifluoro-ethane, also catalysed by antimony pentafluoride, proceeds with concomitant fluorination, and yields j3-chloroperfluoroethylbenzene, CjFj-CFj-CFjCl, and perfluorobibenzy . ... 

There are two main synthetic routes to naphthalene the Haworth synthesis and a Diels-Alder approach. In the Haworth synthesis (Scheme 12.1), benzene is reacted under Friedel-Crafts conditions with succinic anhydride (butanedioic anhydride) to produce 4-oxo-4-phenylbutanoic acid, which is reduced with either amalgamated zinc and HCl (the Clemmensen reduction) or hydrazine, ethane-1,2-diol and potassium hydroxide (the Wolff-Kischner reaction) to 4-phenylbutanoic acid. Ring closure is achieved by heating in polyphosphoric acid (PPA). The product is 1-tetraione and reduction of the carbonyl group then gives 1,2,3,4-tetrahydronaphthalene (tetralin). Aromatization is achieved by dehydrogenation over a palladium catalyst. 

Ipatieff and coworkers carried out the first alkylation with alkenes and branched and normal chain alkanes (except methane and ethane) in the presence of AlCb as the catalyst. The sulfuric acid catalyzed alkylation reaction of arenes and isoalkanes, developed in 1938, is a still widely used industrial process to produce alkylates with high octane numbers. For synthetic applications, however, Friedel-Crafts-type alkylations of alkenes and alkanes have limited value since they tend to give mixtures of products, including oligomers of alkenes. ... 

Scheme 7.15. A representation of a possible pathway for the production of 1,1,1-trichloro-2-[di(p-chlorophenyl)]ethane (dichlorodiphenyltrichloroethane [DDT]) by the Friedel-Crafts aluminum trichloride-catalyzed reaction of chlorobenzene (C HsCl) with chloral (2,2,2-trichhloroethanal, CI3CCHO).

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