Event

Toward the “Ideal” Synthesis of Ambiguine Alkaloids: Uncovering New Horizons in Organo-Bismuth Chemistry

The total synthesis of a complex molecule is often likened to climbing a mountain—a journey marked by unforeseen obstacles and arduous paths that demand both skill and perseverance, where seemingly straightforward routes can unexpectedly become treacherous. In the postmodern era of organic synthesis, the goal of an “ideal” synthesis extends beyond merely reaching the summit by a short route; it requires doing so through a route that yields broadly useful methods or concepts.  It is with this aspiration that we undertook the synthesis of the ambiguines, a challenging subset of the large hapalindole family of cyanobacteria metabolites. The intricate polycyclic architecture of the ambiguines presents worthy challenges to the state-of-the-art of organic synthesis. In this presentation, I will detail our efforts to achieve a concise synthesis of several ambiguines and discuss how these challenges prompted our exploration of organo-bismuth chemistry—an area we anticipate will have broad utility in organic synthesis.

Viresh Rawal received his PhD under Michael P. Cava from the University of Pennsylvania (1986) and carried out postdoctoral work with Professor Gilbert Stork (Columbia University). He commenced his independent career at Ohio State University in 1988, and in 1995 moved to the University of Chicago, where he is Professor of Chemistry. He has delivered over 300 plenary and invited lectures and his work has been recognized through several awards, including the International Society of Heterocyclic Chemistry E.C. Taylor Award (2022) and the ACS Award for Creative Work in Organic Synthesis (2024).