Batch and flow photochemical benzannulations based on the reaction of ynamides and diazo ketones. Application to the synthesis of polycyclic aromatic and heteroaromatic compounds

N-tosyl-3-azacyclohexyne. Synthesis and chemistry of a strained cyclic ynamide

The first synthesis of a strained six-membered cyclic ynamide is described. N-Tosyl-3-azacyclohexyne is generated via fluoride-promoted 1,2 elimination under conditions that allow trapping of the strained heterocyclic alkyne in a variety of addition, insertion, and [2 + 2], [3 + 2], and [4 + 2] cycloaddition reactions.

Photochemical transformations accelerated in continuous-flow reactors: basic concepts and applications

Continuous-flow photochemistry is used increasingly by researchers in academia and industry to facilitate photochemical processes and their subsequent scale-up. However, without detailed knowledge concerning the engineering aspects of photochemistry, it can be quite challenging to develop a suitable photochemical microreactor for a given reaction. In this review, we provide an up-to-date overview of both technological and chemical aspects associated with photochemical processes in microreactors. Important design considerations, such as light sources, material selection, and solvent constraints are discussed. In addition, a detailed description of photon and mass-transfer phenomena in microreactors is made and fundamental principles are deduced for making a judicious choice for a suitable photomicroreactor. The advantages of microreactor technology for photochemistry are described for UV and visible-light driven photochemical processes and are compared with their batch counterparts. In addition, different scale-up strategies and limitations of continuous-flow microreactors are discussed.