Aluminium chloride, complexes from

BenZotrichloride Method. The central carbon atom of the dye is supphed by the trichloromethyl group from iJ-chlorobenzotrichloride. Both symmetrical and unsymmetrical triphenyhnethane dyes suitable for acryhc fibers are prepared by this method. 4-Chlorobenzotrichloride is condensed with excess chlorobenzene in the presence of a Lewis acid such as aluminium chloride to produce the intermediate aluminium chloride complex of 4,4, 4"-trichlorotriphenylmethyl chloride (18). Stepwise nucleophihc substitution of the chlorine atoms of this intermediate is achieved by successive reactions with different arylamines to give both symmetrical (51) and unsymmetrical dyes (52), eg, N-(2-chlorophenyl)-4-[(4-chlorophenyl) [4-[(3-methylphenyl)imino]-2,5-cyclohexadien-l-yhdene]methyl]benzenaminemonohydrochloride [85356-86-1J (19) from. w-toluidine and o-chloroaniline. 

Intermolecular Hydride Ion IVansfer from Alkane to the Acyl Chloride-Aluminium Chloride Complex and Acylation of the Resulting Alkene... 

The donor-acceptor acyl chloride-aluminium chloride complex is not only an electrophilic reagent but also a hydride ion acceptor (oxidizing reagent). The best hydride donors are the saturated hydrocarbons, specially those containing a tertiary carbon atom. The acylation of cyclohexane is an old and well-known reaction giving acetyl-methyl-cyclopentene and/or -cyclopentane. 26,27 the yields are low because the solvent used was either cyclohexane itself or small quantities of chloroform. in our hands, we found that the reaction carried out in methylene chloride solution ( IM) led to the l-acetyl-2-methylcyclopentene and l,3-diacetyl-2-methylcyclopentene Z in good yields. A cleaner reaction also occurred from methylcyclopentane. The ratio of ys could be changed by modification of the reaction conditions (see Table 1) (overall yields of the hydrocarbons functionalization were around 75-80 %). 

The presence of by-products such as 1-chloro-ethyl acetate 3 and a small amoimt of ethyl acetate, suggests that the initial step is an intermolecular hydride ion transfer from cyclohexane or methylcyclopentane towards acetyl chloride-aluminium chloride complex to give 1-methylcyclopentene. From cyclohexane, the cyclohexyl cation isomerizes to 1-methyl-l-cyclopentyl carbenium ion which loses a proton. Then, the 1-chloro-ethylate-aluminium chloride... 

The ob tent ion of pentalenone may result from an acylation by crotonyl chloride of methylcyclopentene generated in situ. The first intermediate gives the divinvlke tone-aluminium chloride complex precursor of the Nazarov reaction followed by cyclization, then hydride and methyl migrations. In this process, the electrophilic and oxidizing reactivities of acyl chlorides are dissociated since acetyl chloride induces the hydride ion transfer and alkenoyl chloride performs the acylation reaction. 

The best yield observed in the in situ reaction could result from the obtention of the divinyl-ketone-aluminium chloride complex directly from the first intermediate and not from the divinyl-ketone 7. 

It should be noted that the Friedel-Crafts acylation differs from the Friedel-Crafts alkylation (compare Sections IV,3-4 and discussion preceding Section IV,1) in one important respect. The alkylation requires catal3d.ic quantities of aluminium chloride, but for acylation a molecular equivalent of aluminium chloride is necessary for each carbonyl group present in the acylating agent. This is because aluminium chloride is capable of forming rather stable complexes with the carbonyl group these complexes probably possess an oxonium... 

Aluminium can be deposited from complex organic solutions if sufficient precautions are taken, and such coatings are now being produced commercially in North America. Two of the systems on record are (1) aluminium trichloride and lithium aluminium hydride dissolved in diethyl ether used at 40°C and 50A/m, and (2) aluminium chloride, n-butylamine and diethyl ether used at 20°C and 970 A/m. Deposits of 0-010 mm can be obtained on mild steel or copper at 20°C and 970 A/m using aluminium-wire anodes and nitrogen or argon atmospheres. 

In these experiments the concentration of aluminium chloride was 2 x 10 3 mole/1. In further experiments [2g], with the complex AlCl3,EtOH at a concentration of 24.6 x 10 3 mole/1. Zlamal and Kazda found that the DP of the polyisobutenes did not change significantly as the proportion of benzene in the solvent was raised from 0 to 15%. This is entirely in agreement with expectation based on our theory. 

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