Tools and techniques for solution‐phase structural understanding of SmI2–additive complexes

SmI2 is a versatile reducing agent for organic synthesis. Additive‐induced tailoring of reaction mechanisms and products is one of the most promising aspects of this multifaceted reagent. In most instances, additives form a coordination complex with SmI2. Insight on the solution‐phase structure of SmI2 in the presence of additives is significant to decipher possible reaction mechanisms and predict reactivity of SmI2 in the presence of an entirely new additive. A series of experimental and computational tools are used to unravel the solution‐phase structure of SmI2–additive complex. This review aims to provide a comprehensive overview of how different analytic tools are employed, and data are analyzed to arrive at a possible solution‐phase structure of SmI2–additive complex. Understanding of SmI2–additive solution‐phase structure in predicting SmI2 reactivity and plausible reaction mechanism is also discussed. SmI2 is pivotal reductant in synthetic organic chemistry due to its unique ability to carry out numerous coupling, cyclization, and radical cascade reactions of high synthetic importance. The chemistry of SmI2 can be fine‐tuned by using additives which form coordination complexes with SmI2. This review focuses on the tools and techniques that are commonly used to decipher solution‐phase structure of SmI2–additive complex.