Progression of Hydroamination Catalyzed by Late Transition-Metal Complexes from Activated to Unactivated Alkenes

• DOI: 10.1021/acs.accounts.3c00141
• Publication Date: 2023-06-05T15:00:23Z
• Authors: Senjie Ma; John F. Hartwig
• Keywords: Hydroamination; Markovnikov's rule; Alkene; Cationic polymerization

ConspectusCatalytic intermolecular hydroamination of alkenes is an atom- and step-economical method for the synthesis amines, which have important applications as pharmaceuticals, agrochemicals, catalysts, materials. However, hydroaminations in high yield with selectivity are challenging to achieve because these reactions often lack a thermodynamic driving force accompanied by side reactions, such alkene isomerization, telomerization, oxidative amination. Consequently, early examples were generally limited additions N-H bonds conjugated or strained alkenes, catalytic unactivated late transition metals has only been disclosed recently. Many classes including metals, rare-earth acids, photocatalysts, reported hydroamination. Among them, transition-metal complexes possess several advantages, their relative ease handling compatibility substrates containing polar sensitive functional groups.This Account describes progression our laboratory catalyzed from initial activated more recent alkenes. Our developments include Markovnikov anti-Markovnikov vinylarenes palladium, rhodium, ruthenium, dienes trienes nickel hydroanimation bicyclic neutral iridium, terminal internal cationic iridium ruthenium. Enantioselective form enantioenriched, chiral amines also developed.Mechanistic studies elucidated elementary steps turnover-limiting reactions. The nickel, ruthenium occurs nucleophilic attack amine on coordinated benzyl, allyl, alkene, arene ligand. On other hand, unconjugated migratory insertion into metal-nitrogen bond. In addition, pathways formation products, isomeric enamines, identified during studies. During enantioselective hydroamination, reversibility shown erode enantiopurity products. Based mechanistic understandings, new generations catalysts that promote higher rates, chemoselectivity, enantioselectivity developed. We hope discoveries insights will facilitate further development selective, practical, efficient