Cyclohexene from anisole

Fig. 27 Formation of enantio-enriched cyclohexenes from a chiral anisole precursor...

The formation of certain ethers can also be accomplished with hydrogen fluoride. Anisole rather than methylphenol results from a reaction between phenol and methyl alcohol at elevated temperature (Simons and Passino, 40). The addition of an olefin to an alcohol to form an ether was shown to occur in the reaction between cyclohexene and cyclohexanol for form dicyclohexyl ether (Simons and Meunier, 66). 

Scheme 18. Preparation of a 2-cyclohexene-l-one complex from a 2,3-i)2-anisole complex.

However, the presence in the anolyte of an anion, which oxidises more readily than the organic substrate and which appears in the substituted product, does not preclude ionisation of the substrate as the operative mechanism. Thus Parker and Burget showed that cyanation of anisole does not proceed at potentials where only cyanide is electroactive ionisation of the anisole is a prerequisite for substitution. " A further example is the chlorination of cyclohexene where, by operating at high electrode potentials at which the olefin is electroactive, chloride ion can be intercepted en route to the anode surface by cyclohexene radical cations diffusing away from it. ... 

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