Abstract
Oxygen and nitrogen heterocycles are present in a vast number of natural substrates and biologically active molecules. In particular, phthalan and isoindoline subunits are found in many classes of products such as antibiotics, antioxidants, antimycotics, pigments, and fluorophores. Therefore several procedures dedicated to the construction of these heterocycles have been developed. In this review, a detailed analysis of the literature data regarding the synthesis of these nuclei via cyclization reactions is reported.
1 Introduction
2 Phthalans
2.1 Oxa-Pictet–Spengler Reaction
2.2 Garratt–Braverman Cyclization
2.3 Diels–Alder and Related Reactions
2.4 [2+2+2] Cyclotrimerization of Alkynes
2.5 Cycloetherification of ortho-Substituted Aromatics
2.6 Tandem Carbonylative Sonogashira Coupling–Cyclization Reactions
3 Isoindolines
3.1 Amination of Dihalides
3.2 Intramolecular Hydroamination
3.3 Diels–Alder and Related Reactions
3.4 [2+2+2] Cycloaddition Reactions
3.5 Tandem Carbonylative Sonogashira Coupling–Cyclization Reactions
4 Conclusions
Key words
phthalan - isoindoline - cyclization - transition-metal catalysis - Sonogashira reaction