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A general and atom-efficient continuous-flow approach to prepare amines, amides and imines via reactive N-chloramines.

ABSTRACT: Chloramines are an important class of reagents, providing a convenient source of chlorine or electrophilic nitrogen. However, the instability of these compounds is a problem which makes their isolation and handling difficult. To overcome these hazards, a continuous-flow approach is reported which generates and immediately reacts N-chloramines directly, avoiding purification and isolation steps. 2-Chloramines were produced from the reaction of styrenes with N-alkyl-N-sulfonyl-N-chloramines, whilst N-alkyl or N,N'-dialkyl-N-chloramines reacted with anisaldehyde in the presence of t-BuO₂H oxidant to afford amides. Primary and secondary imines were produced under continuous conditions from the reaction of N-chloramines with base, with one example subsequently reduced under asymmetric conditions to produce a chiral amine in 94% ee.

SUBMITTER: Jolley KE

PROVIDER: S-EPMC6122332 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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A general and atom-efficient continuous-flow approach to prepare amines, amides and imines via reactive N-chloramines.

Jolley Katherine E KE Chapman Michael R MR Blacker A John AJ

Beilstein journal of organic chemistry 20180824

Chloramines are an important class of reagents, providing a convenient source of chlorine or electrophilic nitrogen. However, the instability of these compounds is a problem which makes their isolation and handling difficult. To overcome these hazards, a continuous-flow approach is reported which generates and immediately reacts N-chloramines directly, avoiding purification and isolation steps. 2-Chloramines were produced from the reaction of styrenes with N-alkyl-N-sulfonyl ...[more]

PMID: 30202475

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