Studies Towards Stereoselective C C C Heteroatom Bond Formations of Strained Rings

Abstract

Chapter I. General introduction to ring opening and cyclization of D-A cyclopropanes newlineNitrogen- and oxygen-containing heterocycles are among the most prevalent moieties found in both pharmaceutical and naturally occurring compounds. Research and development into these compounds is of high interest and of ongoing importance in organic synthesis. Recently, C-C and C-heteroatom bonds newlineformation by ring expansion of three-membered strained ring systems, particularly in D-A cyclopropanes have provided a great synthetic space for easy access to structurally complex scaffolds. The inherent ring strain and electrophilic character made them an attractive building blocks for the selective synthesis of five, six and seven-membered heterocycles through ring-scission. In this chapter, the studies behind the background, reactivity and synthetic methodologies of ring-opening and cyclization of D-A cyclopropanes are discussed.