Chemical synthesis has always attracted researchers because of its beauty and organic synthesis is the active choreography of molecules. This was stated by Prof. Goverdhan Mehta, Director, Indian Institute of Science, Bangalore at the second Prof. K. Venkataraman Memorial Lecture on "Design of new molecular objects: Art and logic in organic synthesis." The lecture was organized by NCL Research foundation in the memory of Prof. K. Venkataraman, who was the first Indian Director, of NCL during 1957 - 1966.
He spoke about new objects unleashed by human imagination and instincts and tried to draw similarities between symmetry of nature and symmetry of molecules created by organic synthesis. He touched upon similarity between curry bowls as molecular objects and demonstrated how these molecular bowls including hetero bowls can be accessed efficiently by creative imagination. He also elicited their fascinating symmetry properties seen during molecular stacking in solid state.
He said that the fullerene, one of the most studied molecules, is the organic chemist's dilemma. On fullerene, around 14000 research papers have been published in last ten years ultimately leading to awarding of noble prize. He elicited the unusual properties of the curves of aromatic surfaces and described how one can access these complex structures of fullerenes and bucky bowls by simple short and general methods involving only three steps of which two steps are devoid of any chemical reagents and can be accomplished by mere photochemical reaction and thermal activation.
He also elicited the strength of covalent self-assembly process involving cascade cyclization to create rings up to C-60 hydrocarbons. He also demonstrated the effectiveness of scientific ingenuity in creating unique ladder like structures, "Ladderanes", in nanometric domain. ``To construct ring and ring making is a kind of great attraction to organic chemist. Square shape is the basic building block in geometry and it can be used in organic chemistry as possible pre-curser to make ladder like structures,'' said Prof. Mehta.
Ladderanes are linearly fused cyclo-butanes and these molecular ladders can act as molecular gates for energy and electron transfer due to their excellent rigid molecular and spacer arrays, added he. He also demonstrated how variety of these ladderanes could be efficiently synthesized by judicious choice of functional groups and largest assembly of fused carbocyclic rings can be easily accessed by this protocol.
He also stressed upon how scientific concept can lead to synthesis of molecular structure unknown to human being. His synthesis of ladderanes, which was conceptualized 10 years before it was found in nature, exhibiting important biological properties of preventing spread of toxic materials due to their shape, is indeed a remarkable and one of the rarest accomplishments.
Earlier, Dr. S. Sivaram, Director, NCL welcomed the audience and in his opening remarks and gave an outline of the Prof. K. Venkataraman's seminal contribution to the chemistry of synthetic dyes and natural products. Prof. Venkataraman was the first Indian director of NCL. Dr. Sivaram appreciated his great vision and leadership qualities.