A convenient preparation of functionalized 1,8-dioxygenated naphthalenes from 6-alkoxybenzocyclobutenones.
An alternate route for the synthesis of naphthalene building blocks 1-4 has been developed, starting from readily available 6-alkoxybenzocyclobutenones. As thermolysis of a propynylbenzocyclobutenol only provided the naphthalene in low yield, allenyl-substituted benzocyclobutenols were investigated. The desired allenic precursors were prepared by a two-step procedure, which involved hydroxyl-directed reduction of the chloropropargylbenzocyclobutenols obtained from addition of lithiopropargyl chloride to the benzocyclobutenones. Thermolysis of the allenic alcohols gave the desired naphthalenes in good yields.
Bungard
Christopher J
CJ
Department of Chemistry, University of Canterbury, Christchurch, New Zealand. j.morris@chem.canterbury.ac.nz
Morris
Jonathan C
JC