A cobalt-catalysed C–H carbonylation of aliphatic carboxamide derivatives is described, employing commercially available Co(ii)-salts in the presence of a silver oxidant.

Abstract:The dream of chemists to imitate the efficiency of Nature for the construction of complex molecules from simple starting materials has driven the development of new concepts in the area of catalysis. In this context, "Multicomponent and Multicatalytic Reactions" have emerged as a highly valuable synthetic tool. These reactions try to mimic the way the enzy-

Cyclic alkenyl triflates are useful intermediates in organic synthesis usually synthesized from ketones through a reaction involving enolization and trapping with a triflating agent. This sequence suffers from some stereochemical drawbacks owing to the basic conditions required. Herein, we describe a new acid-mediated cationic cyclization reaction of enyne derivatives (or alkynols) to access cyclic alkenyl triflates. This new atom-economical process is high yielding, scalable, technically very simple, proceeds without the need of any metallic reagent or catalyst, and more importantly, it complements and challenges conventional methodologies. We have also developed new biomimetic cationic cyclization reactions to yield interesting polycyclic compounds. As a demonstration of the potential of this method in the context of total synthesis, we have synthesized two terpenes: austrodoral and pallescensin A. Using the cationic cyclization in the key step of the synthetic routes allowed the synthesis of these natural products in a very simple, concise, scalable, and efficient way.

An efficient preparation of the antimalarial drug candidate OZ439, which was obtained by integrating a machine-assisted approach with batch processes, is reported. This approach allows a rapid and cost-effective production of the key intermediates that were readily elaborated into the target molecule.

Complex heterocyclic products were synthesized from simple alkynamine and alkynol derivatives in a double cycloisomerization/heterodimerization cascade reaction. The reaction includes the heterocoupling reaction of two different electron-rich alkenes and leads to the formation of four new bonds and three stereocenters (two of them quaternary).