Conversion of Phenols into Aryl Tert-Butyl Ethers Under Mitsunobu Conditions Utilizing Neighboring Group Contribution

Branching out: redox strategies towards the synthesis of acyclic α-tertiary ethers

“…312 Bracher also reported the unexpected formation of aryl-alkyl a-tertiary ethers when employing 4-hydroxy-N-Boc piperidines as substrates under Mitsunobu conditions. 313 In a strategically distinct approach, Mukaiyama focused heavily on phosphorus-mediated oxidation-reduction condensations which can be exploited to condense alcohols to the corresponding ethers (Scheme 80). 314,315 While early reports demonstrated that use of triphenylphosphine as the reducing agent was less compatible with tertiary ether formation, the use of alkoxydiphenylphosphines was found to be much more successful.…”

“…312 Bracher also reported the unexpected formation of aryl–alkyl α-tertiary ethers when employing 4-hydroxy- N -Boc piperidines as substrates under Mitsunobu conditions. 313…”