Development of new reaction methodologies using palladium catalysts

Abstract

Chapter 1: This chapter provides a brief review of the chemistry of metal catalyzed C-C sigma-bond activation reactions. Literature examples for a variety of methods to activate C-C sigma-bonds and their limitations are discussed in detail. Introduction to C-CN sigma-bond reaction and its advantages over the typical C-C sigma-bond activation reactions are discussed with literature examples. Motivation for the current work is also presented.Chapter 2: Presented herein development of new reaction methodology, intramolecular cyanoesterification of alkynes to synthesize highly functionalized butenolides. The reaction proceeds with commonly used palladium catalyst (Pd(PPh3)4) under microwave conditions in five minutes. The reaction tolerates wide variety of substrates and corresponding results are presented. Plausible mechanistic hypothesis is also discussed. Chapter 3: Presented herein new methodology for intramolecular cyanoacylation of alkenes to synthesize highly functionalized indanones . The major challenge of decarbonylation has been overcome using iminonitriles. The reaction proceeds in the presence of commonly used palladium catalyst (Pd(PPh3)4) and very common Lewis acid ZnCl2. The reaction tolerates wide variety of substrates and corresponding results are presented. Results of mechanistic study of the reaction and plausible mechanism are also presented.Chapter 4: Presented herein our attempt towards development of intramolecular azidocyanation of alkenes using carbamoyl azides. Interestingly instead of azidoacylation product, 2-quinazolinone was isolated by the loss of CH2 and N2. Future work on optimization and applications of this interesting reaction are discussed.