Part I: Studies on C-C bond formation reactions : synthesis of imino acid derivatives. Part II: Synthetic studies towards the total synthesis of estrone

Abstract

C-C bond formation reactions are among the most important processes in organic chemistry. Furthermore, C-C bond formation through cross-coupling between two different organic components is a basic technology in organic syntheses. Compounds containing heteroatoms, such as nitrogen, are widely present in nature. The syntheses of these compounds have already attracted much attention in industrial research due to their biological and pharmaceutical properties. In this regard, we focused our efforts to explore the synthesis of imino acid derivatives though direct coupling reactions. Alkanes as Nature’s most abundant organic molecular, have attracted increasing attention on their transformations. However, functionalization of alkanes to imino acid derivatives which may serve as important structural components of biologically active compounds has not been well studied. Therefore, an efficient free radical-initiated reaction of simple cycloalkanes with iminoglyoxylates without involving metal catalysts was developed in Chapter 1, which allowed the functionalization of alkanes to useful imino acid derivatives.Alkynes are very useful building blocks for the synthesis of diverse compounds, especially through metal-promoted reactions. In Chapter 2, a reaction of terminal alkynes with cyclic iminoglyoxylate was described, which affords either propargylic or allylic imino acid derivatives. Meanwhile, an insight into the mechanistic pathway is also discussed.To make this strategy more synthetically useful, a simple and efficient direct coupling reaction of terminal alkynes with cyclic iminoglyoxylate using CuCl as a catalyst, FeCl3 as a co-catalyst and TEMPO as an oxidant was also developed.