Ligand‐Controlled Copper‐Catalyzed Regiodivergent Carbonylative Synthesis of α‐Amino Ketones and α‐Boryl Amides from Imines and Alkyl Iodides

Abstract

Regioselective transformation is among the long‐standing challenges in organic synthesis. In this communication, a copper‐catalyzed selectivity controlled regiodivergent borocarbonylation of imines with alkyl iodides has been developed. Various α‐amino ketones and α‐boryl amides were produced in moderate to good yields from the same substrates. The choice of the ligand is key for the regioselectivity control: α‐amino ketones were produced selectively in good yields with (p‐CF3C6H4)3P as the ligand, whereas the corresponding α‐boryl amides were obtained with high regioselectivities when using MeIMes as the ligand.

Non‐Noble Metal‐Catalyzed Carbonylative Multi‐Component Reactions

“…Under the assistance of Me IMes ligand, complex A quickly reacts with alkyl iodide to intermediate C, after CO insertion and reductive elimination to give the final α-boryl amides 23. [17] CO as both carbonyl source and methylene source in multicomponent carbonylation was disclosed by Wu and co-workers. γ-Boryl esters were prepared from the β-substituted styrenes and alcohols in moderate to good yields, via carbonylative borofunctionalization in the presence of CuI and dppe catalytic system (Scheme 16).…”

“…The N−Cu bond of complex A tends to undergo intramolecular 1,2‐rearrangement to afford α‐amino alkyl‐copper complex B in the case of electron‐deficient ligand, then producing the α‐amino ketones 22 . Under the assistance of Me IMes ligand, complex A quickly reacts with alkyl iodide to intermediate C , after CO insertion and reductive elimination to give the final α ‐boryl amides 23 [17] …”

Catalyst-controlled selective borocarbonylation of benzylidenecyclopropanes: regiodivergent synthesis of γ-vinylboryl ketones and β-cyclopropylboryl ketones

“… 6 To date, borocarbonylation reactions have been reported with alkenes, alkynes, and imines. 7 The reported borocarbonylation of alkenes was limited to styrenes and did not allow for regioselectivity control. 7 b Thus, variants involving methylenecyclopropanes 8 are particularly attractive because of the potential to control the formation of various boryl ketones.…”

Regiodivergent Organocatalytic Reactions

“…Regiodivergent synthesis reactions, which enable two or more regioisomeric products to be synthesized from the same starting material, are controlled by various reaction parameters such as catalysts, additives, solvents, temperatures, ligands, and functional groups [49,50]. Although several metal-catalyzed regiodivergent reactions have been thoroughly studied [51][52][53][54][55], organocatalytic regiodivergent reactions have not been explored [56]. This mini review of organocatalytic regiodivergent reactions is intended to fill this void.…”