A formal [4 + 4] complementary ambiphile pairing reaction: a new cyclization pathway for ortho-quinone methides.

A formal, one-pot [4 + 4] cyclization pathway for the generation of eight-membered sultams via in situ generation of an ortho-quinone methide (o-QM) is reported. The pairing of ambiphilic synthons in a complementary fashion is examined whereby o-fluorobenzenesulfonamides are merged with in situ generated o-QM in a formal [4 + 4] cyclization pathway to afford 5,2,1-dibenzooxathiazocine-2,2-dioxide scaffolds under microwave (mW) conditions. The method reported represents the first use of an o-QM in a formal hetero [4 + 4] cyclization.