Aluminium trichloride/methylene chloride

When methylene chloride solutions of the alkene and aluminium trichloride were mixed a yellow solid precipitated. The precipitate contained both alkene and aluminium trichloride. Except for the cyano absorption the IR spectrum of the alkene in the precipitate is unchanged. Aluminium trichloride has co-ordinated to the cyano groups but not broken the double bond - a betaine has not been formed. The complex appears to be polymeric, it will not dissolve in polar aprotic solvents. However, it will dissolve in chloroform without chemical reaction if a little methanol is added. Apparently, the polymeric structure is disrupted by methanol co-ordination. The HNMR (in CDC13) spectrum shows that one molecule of alkene dissolves per molecule of alcohol. Despite the proximity of an alcohol molecule to the strongly polarized alkene no chemical reaction takes place in this solvent. 

Also obtained by selective demethylation of 2,3 -dimelhoxybenzophenone in the presence of boron trichloride in methylene chloride at r.t. for 30 min [341,343]. Also obtained (poor yield) by reaction of 3-methoxybenzoyl chloride with ani-sole in the presence of aluminium chloride in refluxing carbon disulfide for 2 h [341]. 

Preparation by reaction of acetonitrile on phenol with aluminium chloride and boron trichloride in refluxing ethylene dichloride (78%) [4549] or in methylene chloride at r.t. (85%) [4550],... 

The bridgehead fluorines of the diene (111) are susceptible to electrophilic displacement. Thus it reacts with aluminium trichloride in methylene chloride to give the 1-chloro- and 1,4-dichloro-derivatives (122) and (123) respectively in methyl iodide solution, the l-chloro-4-iodo-derivative (124) and di-iodide (125) are also formed, and with aluminium tri-iodide in methyl iodide, a small amount of 1-iodo-compound (126), together with di-iodide (125), is produced. Both the chloro-compounds (122) and (123) photochemically add only one mole of bromine. As expected, the oleflnic fluorines of compound (111) may be displaced by nucleophiles. Methyl-lithium gives a mixture of... 

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