Development of the scope of a co-mediated O-->C rearrangement reaction.
[reaction: see text] In this paper we describe an Al-promoted, Co-mediated O-->C rearrangement reaction of cyclic enol ethers. This process delivers functionalized cyclohexanones with good to excellent levels of diastereocontrol, whereby the product stereochemistry is dependent on the E/Z-stereochemistry of the starting enol ether. The rearrangement process also permits access to highly substituted alpha-spirocyclic cyclohexanones as well as cyclopentanones. The latter rearrangement appears to proceed via an unusual 5-(enolendo)-exo-trig cyclization process.
Meek
Simon J
SJ
Department of Chemistry, University of Sheffield, Brook Hill, Sheffield, S3 7HF, UK.
Pradaux
Fabienne
F
Carbery
David R
DR
Demont
Emmanuel H
EH
Harrity
Joseph P A
JP
D000535:Aluminum / Q000737:chemistry; D003035:Cobalt / Q000737:chemistry*; D004988:Ethers, Cyclic / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
D004988:Ethers, Cyclic; D009942:Organometallic Compounds; D003035:Cobalt; D000535:Aluminum