Cyclohexadienones. Use of the dienone–phenol rearrangement in measuring migratory aptitudes of alkyl groups
Abstract
Kinetic and product studies of the rearrangements in aqueous sulphuric acid of selected cyclohexa-2,5-dienones are used to measure the migratory aptitudes in this carbonium-ion rearrangement of the methyl, ethyl, and n-propyl groups. The rearrangement of 4a-ethyl-5.6,7.8-tetrahydronaphthalen-2(4aH)-one in aqueous sulphuric acid has been reinvestigated. It is demonstrated that the lanthanide shifts brought about by Eu(fod)3 on the n.m.r. spectra of isomeric alkylphenols have great value in structure determination.