Transannulation as a Tactic in Natural Product Synthesis: DFT Study on Bielschowskysin

Abstract

My research work was focused on transannular studies as a tactic in natural product synthesis and proposed various synthetic methods to obtain the polycyclic systems from common macrocyclic intermediate. The macrocyclic intermediate was designed to obtain via Nozaki-Hiyama-Kishi reaction as key step; the key alkyne fragment was prepared using the Corey-Fuch reaction starting from L-tartaric acid. In the later chapter, I mainly focused on DFT studies to rationalize synthetic routes of bielschowskysin. Feasibility of transannular 2+2 cycloaddition reaction and macrocyclization from the linear precursor was evaluated by DFT calculations. The molecular structure and vibrational frequencies of the title compound in the ground state have been investigated with ab-initio DFT method B3LYP implementing the standard 6-31G(d) basis set, determined the total energy, enthalpy and free energy of the reaction.