Asymmetric Total Synthesis of Mycoleptodiscin A

Regiodivergent Remote Arylation of Cycloalkanols to Dysideanone's Fused Carbotetracycles and Its Bridged Isomers

Regiodivergent γ and γ' arylations across an all-carbon quaternary center of cycloalkanols to access enantioenriched fused and bridged carbotetracycles are reported. The conformation of the carbocation guided either sequential stereospecific β-C-Me/γ-C-H-shifts or β-C-Me/γ'-C-H-shifts, providing fused carbotetracyclic analogs of dysideanone or bridged tetracycles, respectively. The reaction is highly stereoselective in building three contiguous stereocenters, where one, two, or three could be all-carbon quaternary centers. Interestingly, mechanistic studies revealed a crucial role of a methyl substituent in controlling regioselectivity.