Studies on carbo- and amino functionalization of alkenes by conjugate addition and hydroamination
Tong, Benny Meng Kiat
Date of Issue2014
School of Physical and Mathematical Sciences
This dissertation describes studies on carbo- and amino-functionalization of alkenes using conjugate addition and hydroamination strategy. In Chapter 1, the importance and chemical functionalization of alkenes are highlighted in Chapter 1. Chapter 2 describes development of a methodology that employs organic diamine as catalyst for conjugate addition reactions of active methine nucleophiles to acrylate derivatives. It could be speculated that hydrogen bonding plays a vital role to activate the less reactive acrylate derivatives towards conjugate addition. Chapter 3 entails a domino SN2-conjugate addition sequence for the diastereoselective synthesis of various carbocyclic compounds. The strategy is applied for synthesis of bicyclic lactone derivatives including biologically active natural products, dihydronepatalactone, isodihydronepetalactone and 1-epi-isodihydronepetalactone. Chapter 4 describes a method for synthesis of cyclic nitrones using alkenyl oximes based on inorganic base-mediated hydroamination. DFT calculations of the reaction pathway suggested that the present hydroamination could proceed via unprecedented nucleophilic amination of unactivated alkene by the oxime nitrogen, the transition state of which is stabilized by ionic interaction of the metal cation such as K+ on the oxime oxygen and negatively charged alkene moiety.