Acyl migrations in Diels–Alder adducts of acyl-1,4-benzoquinones
作者:Faujan B. H. Ahmad、J. Malcolm Bruce、Jabbar Khalafy、Vjera Pejanović(née Bajić)、Khojasteh Sabetian、Ian Watt
DOI:10.1039/c39810000166
日期:——
Treatment of several 4a-acyl-4a,5,8,8a-tetra-hydro-1,4-naph thoquinones with boiling acetic anhydride gives the 1,4-diacetoxy-2-acyl-5,8-dihydronaphthalenes, and the corresponding 1,4-dihydroxy-compounds are formed when acetic acid is used, but the latter are more readily obtained, via the Δ8a,1enols, by treatment with pyridine or pyridine–methanol, these basic reagents cause deformylation of the 4a-formyl
Base-induced benzoyl migrations in Diels–Alder adducts of benzoyl-1,4-benzoquinones
作者:Raad Al-Hamdany、J. Malcolm Bruce、Ramchand T. Pardasani、Ian Watt
DOI:10.1039/c39810000171
日期:——
trans-penta-1,3-diene to substituted benzoyl-1,4-benzoquinones affords the corresponding 4a-benzoyl-4a,5,8,8a-tetrahydro-1,4-naphthoquinones which in pyridine and pyridine–methanol, undergo [1,5] and [1,2] benzoyl shifts to give 2-benzoyl-5,8-dihydro-1,4-dihydroxynaphthalenes; the effects of para-substituents in the benzoyl group on the kinetices and regiospecificity of the migration are described.