Cobalt‐Catalysed Reductive Etherification Using Phosphine Oxide Promoters under Hydroformylation Conditions
作者:Fábio G. Delolo、Johannes Fessler、Helfried Neumann、Kathrin Junge、Eduardo N. dos Santos、Elena V. Gusevskaya、Matthias Beller
DOI:10.1002/chem.202103903
日期:2022.2.21
No noble metal needed: The cobalt-catalysed reductive etherification of aldehydes with alcohols under syngas conditions has been investigated and proved to be efficient for a broad range of coupling partners. The promoting effect of phosphine oxides allows for a milder and more general reaction: the methodology presented a good functional group tolerance and could be applied to natural alcohols.
A range of medium-sized cyclic ethers (5 to 11 membered) have been effectively synthesized through intramolecular reductive coupling of dialdehydes initiated by 50 ppm to 0.5% of AgNTf2 with hydrosilane at 25 °C. The catalytic system is also suitable for the coupling of two different monoaldehydes to provide unsymmetrical ethers. This protocol features broad functional group compatibility, high product