Cesium fluoride-mediated claisen rearrangements of phenyl propargyl ethers: Substituent effects of an orthoalkoxy group on the benzene ring or modified propargyl residues
The expected 7-alkoxy-2-methylbenzo[b]furans were effectively given in the CsF-mediated Claisen rearrangement of phenyl propargyl ethers with an o-alkoxy substituent on the benzene ring. On the other hand CsF did not affect the production of the corresponding benzo[b]furans when ethers, carrying a propargyl residue modified by either 1,1-dimethyl or 3-ethoxycarbonyl functions, were used as substrates in the rearrangement.