Ring Saturation of Phenolic Ethers

A Birch reduction of 2-methylanisole leading to methylenation has been described. The final step was effected by treatment of the intermediate, 3,6-dihydro-2-methyl-4-trimethylsilylmethylanisole with concentrated hydrochloric acid and aqueous tetrahydrofuran during 30 hours to give 4-methylene-2-methylcyck)hexanone in 60% yield (ref. 176). 

An additive reaction of a phenolic ether is shown in a one-pot syntheses in which decarboxiation also takes place. 5-(4-Methylphenoxy)-2-furoic acid and N-phenylmaleimide in chloroform containing 10mole% trifluoroaceticacid heated in a sealed thick-walled tube under nitrogen for 1-2 hours gave N-phenyl 

3-(4-methylphenoxy)phthalimide in 95% yield accompanied presumably by loss of water from the reactants (ref. 177). In a similar way 5-alkoxy and 

5-arylthk)-furan-2-carboxylic acids have been reacted. 

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