Gold-catalyzed cycloisomerization strategies for the stereoselective synthesis of carbocycles from alkynes

Abstract

The work in this thesis was undertaken in Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences in Nanyang Technological University from January 2010 to March 2014 under the supervision of Prof. Philip Wai Hong Chan. The work of this thesis has been directed towards establishing gold-catalyzed intramolecular cyclization as novel synthetic strategies to carbocycles. This thesis is divided into three parts:  Part I consists of Chapter I, which gives an introduction to gold catalysis and its application in the cycloisomerization of 1,n-enyne esters and 1,n-diyne carbonates and esters.  Part II is aimed at exploring novel gold-catalyzed cyclization of 1,n-diyne esters and carbonates for the preparation of synthetically useful cyclic organic compounds. Chapter II addresses an efficient gold-catalyzed, expedient and chemoselective approach for the transformation of 1,6-diyne carbonates and esters to 2,4a-dihydro-1H-fluorenes which could be found in a lot of natural and synthetic compounds and functional materials. Chapter III describes an efficient gold-catalyzed cyclization strategy to structurally diverse 1H-cyclopenta[b]naphthalenes, cyclopenten-2-yl δ-ciketones and bicyclo[3.2.0]hepta-1,5-dienes.  Part III contains the experimental data (Chapter V) and references (Chapter VI) pertaining to this thesis.