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Cross-Selective Aza-Pinacol Coupling via Atom Transfer Catalysis.

ABSTRACT: A cross-selective aza-pinacol coupling of aldehydes and imines has been developed to afford valuable β-amino alcohols. This strategy enables chemoselective conversion of aliphatic aldehydes to ketyl radicals, in the presence of more easily reduced imines and other functional groups. Upon carbonyl-specific activation by AcI, a photoinitiated Mn catalyst selectively reduces the resulting α-oxy iodide by an atom transfer mechanism. The ensuing ketyl radical selectively couples to imines, precluding homodimerization by a classical reductive approach. In this first example of reductive, ketyl coupling by atom transfer catalysis, Zn serves as a terminal reductant to facilitate Mn catalyst turnover. This new strategy also enables ketyl radical couplings to alkenes, alkynes, aldehydes, propellanes, and chiral imines.

SUBMITTER: Rafferty SM

PROVIDER: S-EPMC8588569 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Cross-Selective Aza-Pinacol Coupling via Atom Transfer Catalysis.

Rafferty Sean M SM Rutherford Joy E JE Zhang Lumin L Wang Lu L Nagib David A DA

Journal of the American Chemical Society 20210408 15

A cross-selective aza-pinacol coupling of aldehydes and imines has been developed to afford valuable β-amino alcohols. This strategy enables chemoselective conversion of aliphatic aldehydes to ketyl radicals, in the presence of more easily reduced imines and other functional groups. Upon carbonyl-specific activation by AcI, a photoinitiated Mn catalyst selectively reduces the resulting α-oxy iodide by an atom transfer mechanism. The ensuing ketyl radical selectively couples to imines, precluding ...[more]

PMID: 33830738

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