Base-promoted reaction of O-sulfonylated hydroxamic acids with nucleophiles. A new method for the synthesis of .alpha.-substituted amides
摘要:
Treatment of a series of hydroxamic acids 2 with mesyl chloride in the presence of 2 equiv of triethylamine at 0-degrees-C gives 2-chloroamides 3 in good yields. Use of a single equivalent of triethylamine gives the (N-mesyl-oxy)amides 1, which are versatile synthetic intermediates as they can be readily converted to 2-bromoamides 4 with lithium bromide and triethylamine and to 2-hydroxyamides 5 with triethylamine in aqueous acetonitrile.
Efficient conversion of O-sulfonylated arylacetohydroxamic acids to 2-substituted secondary amides
作者:Robert V. Hoffman、Naresh K. Nayyar、Bruce W. Klinekole
DOI:10.1021/ja00041a064
日期:1992.7
Base-promoted reaction of O-sulfonylated hydroxamic acids with nucleophiles. A new method for the synthesis of .alpha.-substituted amides
作者:Robert V. Hoffman、Naresh K. Nayyar、Wenting Chen
DOI:10.1021/jo00047a024
日期:1992.10
Treatment of a series of hydroxamic acids 2 with mesyl chloride in the presence of 2 equiv of triethylamine at 0-degrees-C gives 2-chloroamides 3 in good yields. Use of a single equivalent of triethylamine gives the (N-mesyl-oxy)amides 1, which are versatile synthetic intermediates as they can be readily converted to 2-bromoamides 4 with lithium bromide and triethylamine and to 2-hydroxyamides 5 with triethylamine in aqueous acetonitrile.
Zinc‐Mediated Radiosynthesis of Unprotected Fluorine‐18 Labelled α‐Tertiary Amides
作者:Jay S. Wright、Richard Ma、E. William Webb、Wade P. Winton、Jenelle Stauff、Kevin Cheng、Allen F. Brooks、Melanie S. Sanford、Peter J. H. Scott
DOI:10.1002/anie.202316365
日期:2024.1.8
A high-yielding radiofluorination of unprotected α-tertiary haloamides is described. This method provides a new strategy for radiochemists to install fluorine-18 into sterically protected environments for positronemissiontomographyimaging. Preliminary mechanistic studies were leveraged to develop a novel C−H radiofluorination reaction of N-sulphonyloxyamides.