Dehydrobenzene in the Reaction of a Tandem [4+2]/[4+2] Cycloaddition with Linear bis-furyldienes

[Figure not available: see fulltext.] Tandem [4+2]/[4+2] cycloaddition between bis-dienes containing two furan rings and dehydrobenzene as a dienophile was studied. It was shown that dehydrobenzene generated in situ from 2-(trimethylsilyl)phenyl trifluoromethanesulfonate is capable of a facile intermolecular [4+2] cycloaddition to a furan moiety of a diene at room temperature. The next step, that involves intramolecular Diels–Alder reaction (the IMDAF reaction) with the second furan ring, requires elevated temperature up to 80°С. It has been shown that even under optimal conditions the yields of the target annulated 1,4:5,8-diepoxynaphthalenes do not exceed 50%. The main byproducts are double cycloaddition adducts formed during the interaction of two aryne subunits with both furan rings of the initial bis-diene. © 2021, Springer Science+Business Media, LLC, part of Springer Nature.