Umpolung amide synthesis using substoichiometric N-iodosuccinimide (NIS) and oxygen as a terminal oxidant.

Org Lett

Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37235, United States.

Published: September 2014

Umpolung Amide Synthesis (UmAS) provides direct access to amides from an α-bromo nitroalkane and an amine. Based on its mechanistic bifurcation after convergent C-N bond formation, depending on the absence or presence of oxygen, UmAS using substoichiometric N-iodosuccinimide (NIS) under aerobic conditions has been developed. In combination with the enantioselective preparation of α-bromo nitroalkane donors, this protocol realizes the goal of enantioselective α-amino amide and peptide synthesis based solely on catalytic methods.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4168777PMC
http://dx.doi.org/10.1021/ol502089vDOI Listing

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Article Synopsis
  • The article discusses a new method for synthesizing α-heteroatom-substituted secondary amides, which are important in chemistry but hard to make using traditional techniques.
  • It utilizes a unique umpolung procedure that allows for the functionalization of carbonyl groups at the α-position without needing external oxidants, simplifying the synthesis.
  • The process has strong theoretical backing, showing that a combination of Mg and DIPEA plays a crucial role in forming intermediates, making this protocol the first reliable method for creating these specific amides.
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