Photochemical isomerization pentaatomic heterocyclic

The photochemical isomerization of pentaatomic heterocyclic compounds has been the object of several reviews, starting with that of Lablache-Combier in 1971 (71BSF679). After this work, reviews of the whole field (76MI123 77CRV473 ... 

Recently, we reported our first attempts to reach a unified description of the photochemical isomerization of pentaatomic heterocyclic compounds [99H(50)1115 99MI233]. If the first excited state of a molecule is populated, this molecule can... 

This scheme is very simple if compared with the jungle of hypotheses formulated to justify the photochemical isomerization of pentaatomic heterocycles. I do not know if it is true or if it represents a constriction of the nature in a rigid cage. I hope my work will be useful to direct future research efforts in this field. It is not important if future data will confirm or destroy my hypothesis The most important thing is to elicit a discussion. 

Professor D Auria (Basilicata University) summarizes the photochemical isomerization of pentaatomic heterocycles, providing a unified description in terms of the five conceivable mechanisms. R. Alan Aitken and Andrew W. Thomas of the University of St. Andrews, Scotland, summarize the substantial recent progress in heterocyclic acyl and formyl anion equivalents. 

D Auria, M. (2001) Photochemical isomerization of pentaatomic heterocycles. Advances in Heterocyclic Chemistry, 79, 41-88. 

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