Chapter 2 Radical methods in the synthesis of heterocyclic compounds

TLDR: Heterocycle syntheses, in which radical reactions are used for the key bond construction, are discussed in this chapter, and an interesting method for the preparation of epoxides using radical methodology has been reported.

Abstract: Publisher Summary This chapter discusses radical methods in the synthesis of heterocyclic compounds. Radical reactions have found increased application in the preparation of simple as well as complex heterocyclic compounds. Heterocycle syntheses, in which radical reactions are used for the key bond construction, are discussed in this chapter. An interesting method for the preparation of epoxides using radical methodology has been reported. Formation of five-membered heterocycles through radical methodologies has been investigated extensively. Inter-, intramolecular, and cascade reactions have been reported for the synthesis of heterocycles. In the case of intramolecular cyclizations, 5-exo pathway is the preferred mode of reactivity. Rate constant for the formation of pyrrolidine by radical ring closure has been reported. An efficient modification of the manganese (III) mediated malonate radical addition to styrene has been examined. Intramolecular radical cyclization reactions are extensively used for the formation of heterocycles. These reactions are generally carried out under reductive conditions using tin or silicon hydride reagents. The tin hydride reagent can be used catalytically.