Using Nazarov Electrocyclization to Stage Chemoselective [1,2]-Migrations: Stereoselective Synthesis of Functionalized Cyclopentenones

摘要

Since its discovery in 1941, the Nazarov 4π-conrotatory electrocyclization has become an elegant and efficient way to prepare substituted cyclopentenones with adjacent stereo-genie centers. Although some inroads have been made with respect to asymmetric catalysis or development of new catalytic systems, substrate scope is often quite limited, especially to construct vicinal quaternary centers. To extend the reactivity related to the Nazarov cyclization, several groups have developed new methods involving either the trapping of the oxyallyl cation intermediate by suitable reagents or rearrangements that lead to highly functionalized, synthetically useful cyclopentanone products.