The copper(I)-mediated reaction between five-membered cyclic nitrones and terminal
acetylenes, leading to the assembly of the basic skeleton of carbapenem antibiotics
is described. The diastereoselectivity of this cycloaddition–rearrangement cascade,
a process known as the Kinugasa reaction, with respect to the structure and configuration
of both substrates, as well as the reaction conditions, are discussed. Application
of the described methodology to sugar-derived nitrones offers an attractive entry
toward thienamycin and related compounds.
Key words
β-lactams - Kinugasa reaction - carbapenem antibiotics - nitrones - acetylenes