A Concise Enantioselective Total Synthesis of (?)-Virosaine A

Article abstract of DOI:10.1002/anie.201706273

The total synthesis of (?)-virosaine A (1) was achieved in ten steps starting from furan and 2-bromoacrolein. A one-pot Diels–Alder cycloaddition/organolithium addition initiated an efficient sequence to access a key oxime/epoxide intermediate. Heating this intermediate in acetic acid resulted in an intramolecular epoxide opening/nitrone [3+2] cycloaddition cascade to construct the caged core of 1 in a single step. Several methods of C?H functionalization were assessed on the cascade product, and ultimately, a directed lithiation/bromination effected selective C14 functionalization, enabling the synthesis of 1.