Our asymmetric total synthesis of Lophirone H using an oxonium-Prins key step as completed by Mathias, Sean and Hossay is finally published!

Hossay Abas, Sean M. Linsdall, Mathias Mamboury, Henry S. Rzepa and Alan C. Spivey, ‘Total Synthesis of (+)-Lophirone H and its Pentamethylether Utilizing an Oxonium-Prins Cyclisation’, Org. Lett. 2017, ASAP. DOI: 10.1021/acs.orglett.7b00642

The first total synthesis of (+)-lophirone H 1 and its pentamethylether 29, featuring an oxonium-Prins cyclisation/benzylic cation trapping reaction, is described. This key step allows for the formation of three of the five contiguous stereocentres in the cis-fused 4H-furo[3,2-c]benzopyran core. Enantioselective preparation of the homoallylic alcohol Prins substrate occurs via an Evans-type asymmetric aldol/Heck reaction sequence.