Compounds bearing the isochroman ring system are found in natural and synthetic products of interest. The oxa-Pictet-Spengler condensation is a valuable tool for the preparation of polysubstituted isochromans and related oxygen-bearing heterocycles. The different stagings of the oxa-Pictet-Spengler reaction, as well as the scope and limitations of this transformation, are discussed.
-
1 Introduction
-
2 Intermolecular Oxa-Pictet-Spengler Condensation
-
2.1 Synthesis of 1-Substituted Isochromans
-
2.2 Synthesis of 1,1-Disubstituted Isochromans
-
2.3 Diastereoselective Synthesis of 1,3-Disubstituted Isochromans
-
2.4 Synthesis of 3-Substituted Isochromans
-
2.5 Synthesis of C-4 Substituted Isochroman Derivatives
-
3 Intramolecular Oxa-Pictet-Spengler Cyclizations
-
3.1 Synthesis of 1-Substituted Isochromans
-
3.2 Diastereoselective Synthesis of 1,3-Disubstituted Isochromans
-
3.3 Synthesis of 1,3,4-Trisubstituted Isochromans
-
4 The Oxa-Pictet-Spengler Condensation in the Absence of Acid Catalysts
-
5 Naturally Occurring Oxa-Pictet-Spengler Cyclizations
-
6 Oxa-Pictet-Spengler Reactions towards Optically Active Compounds
-
7 Synthesis of Heterocycles other than Isochroman Derivatives
-
8 Conclusions
oxa-Pictet-Spengler - cyclization - isochromans - natural products - chemical synthesis
