Regioselectivity of Mercury-Promoted Oxacyclizations of Alkynyl DiolsThis material is based upon work supported by the National Science Foundation under CHE-1362249. We also acknowledge the Bruker AVANCE III HD 600 MHz NMR spectrometer, supported by NSF grant CHE-1531620
Received: 22 June 2017
Accepted after revision: 28 July 2017
23 August 2017 (eFirst)
Dedicated in celebration of the 80th birthday of Professor Victor Snieckus
Hg(OTf)2-catalyzed cyclization of an alkynyl alcohol on a tetrahydropyran template gives the bispyranyl ketone arising from dehydrative cyclization and alkyne hydration, rather than the targeted fused pyran-oxepane product. The combination of stoichiometric Hg(OTf)2 and triethylsilane gives reductive cyclization, but affords the fused pyran-oxocane corresponding to an 8-endo-mode oxacyclization process.