Author:

Keywords:

Science & Technology, Physical Sciences, Chemistry, Multidisciplinary, Chemistry, computer chemistry, ligands, magnetic properties, NMR spectroscopy, ruthenium, FITTING BASIS-SETS, HARTREE-FOCK, METAL, DEHYDROGENATION, 4-COORDINATE, REACTIVITY, ENERGY, AMIDO, APPROXIMATION, COORDINATION, CH insertion, carbenes, iodonium ylides, lactams, reaction mechanism, Amides, Benzene Derivatives, Methane, Thermodynamics, beta-Lactams, 03 Chemical Sciences, General Chemistry, 34 Chemical sciences

Abstract:

Carbene intermediates are very useful species for a range of reactions including C-H insertions and cycloadditions. They are most commonly generated by metal-catalyzed release of nitrogen gas from diazo precursors. Herein, we present a novel C-H insertion of simple β-ketoamide substrates, through reaction with (diacetoxyiodo)benzene (DIB) in the presence of a base. This unprecedented transformation bypasses the use of either diazo precursors or metal catalysts and directly delivers β-lactam products by an iodonium ylide, in a single step under mild conditions. Mechanistic studies support the intermediacy of a free singlet carbene of unique reactivity and selectivity.