Polymer mechanochemistry-enabled pericyclic reactions

Electron fluctuation in pericyclic and pseudopericyclic reactions.

Since the very beginning pericyclic reactions have presented difficult mechanistic problems. It was not until Woodward and Hoffmann set up their theory of orbital symmetry conservation that the mechanisms of these reactions clearly showed up. A few years after that, Ross et al. proposed the term “pseudopericylic” to describe a set of reactions which broke the laws given by Woodward and Hoffmann...

7 Reaction mechanisms Part ( ii ) Pericyclic reactions

Research into the mechanisms of pericyclic reactions continues at a rapid pace. Many of the studies described below address the factors which influence whether a reaction will proceed via concerted rearrangement or will follow a stepwise alternative. Numerous papers published this year report high-level computational studies undertaken to explain unusual regiochemistry or stereochemistry determ...

Pericyclic reactions catalyzed by chorismate-utilizing enzymes.

One of the fundamental questions of enzymology is how catalytic power is derived. This review focuses on recent developments in the structure--function relationships of chorismate-utilizing enzymes involved in siderophore biosynthesis to provide insight into the biocatalysis of pericyclic reactions. Specifically, salicylate synthesis by the two-enzyme pathway in Pseudomonas aeruginosa is examin...

Polymer mechanochemistry: Flex, release and repeat.

Unambiguous Assessments of Reaction Paths for Selected Pericyclic Reactions

Three major approaches have been developed to predict outcomes for concerted reactions controlled by orbital symmetry analysis using (i) correlation diagrams1, (ii) frontier orbital interactions in transition states2 and (iii) incipient aromatic/ antiaromatic character in transition states3-5. The latter approach (Zimmerman-Dewar or Hückel-Möbius) is particularly simple to teach to undergraduat...