Kinetics, Thermodynamics, and Emergence in Stereoediting Reactions.

ConspectusThe selective formation of one stereoisomer over another is a long-standing challenge in organic chemistry. Conventionally, the configuration of a stereogenic center is defined during bond forming molecular assembly steps and thereafter treated as a static component of the molecular structure. One isomer is often more accessible than others, because it can be obtained directly from natural sources, because synthetic strategies to access certain stereochemical patterns are more efficient than others, or because substrate-based steric and electronic biases preclude certain reaction outcomes. In such cases, the ability to revise the stereochemistry without altering the underlying molecular skeleton could parlay more accessible products directly into more challenging targets.In this Account, we describe our efforts to develop stereocenter editing tools to enable the interconversion of stereoisomers with a predictable and tunable selectivity. Stereoediting methods developed by our lab leverage radical intermediates accessed by sequential H atom abstraction and donation steps promoted by a range of different H atom transfer reagents. Modern photoredox methods enable access to reactive radical intermediates under mild reaction conditions, serve as an orthogonal stimulus to induce dynamic character from otherwise static structures, and provide ample fuel to drive