Ethers aryl difluoromethyl

B.R. Langlois, Improvement of the synthesis of aryl difluoromethyl ethers and thioethers by using a solid-liquid phase-transfer technique, J. Fluorine Chem. 41 (2) (1988) 247-261. 

As depicted in Equation (97), oxidative cross-coupling of a-aryl-/3,/3-difluoroenol silyl ether with unfunctionalized benzo[ ]furan 82 in the presence of Cu(OTf)2 in wet acetonitrile proceeded smoothly to give benzo[/ ]furan difluoromethyl aryl ketone in 50% yield <2004OL2733>. 

Difluoromelhyl)dimethylphenylsilane, in the presence of a catalytic source of fluoride, reacts eificiently with aryl and alkyl aldehydes to produce difluoromethyl alcohols, e.g. 12.On the other hand, it has been reported - that (difluoromethyl)dimcthylphenylsilane reacts with some carbonyl compounds under these conditions to give only silyl enol ethers. The authors suggested that destabilization of the negative charge at the a-carbon by the difluoromethyl fragment induces enolization. 

Fluorinated methyl aryl ethers. The facile rearrangement of oxygenated benzyl derivatives effected by XeFa to give fluorinated methyl ethers, i.e., benzyl alcohols to fluoromethyl aryl ethers and benzaldehydes to difluoromethyl aryl ethers, may involve the formation of fluoroxy intermediates and thence oxaspirobenzenium ions. 

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