Beyond Achmatowicz reaction: DDQ-mediated chemo- and stereoconvergent domino-one pot cyclization/rearrangement of bis-thioenol ether-containing chiral building blocks

A highly convergent multistep process incorporating an aza-Achmatowicz rearrangement has been described, selectively providing enantiomerically pure bicyclic (dihydro)furans 9 and 18 as well as the tricyclic dihydropyridinone 23 from acyclic starting materials after up to eight sequential synthetic transformations in one step