CHEMICAL sciences represent an unique position among the different disciplines in science. The versatility of chemistry lies in the ease with which it forms overlap regions with other disciplines such as biology, medicine, physics, engineering and others. The overlap regions form a rich resource for diverse applications of science to humanity. Chemistry embodies many branches of research pursuits such as organic chemistry (chemistry of carbon compounds, in general), inorganic chemistry (chemistry of metals and non metals), physical chemistry (a study of why and how chemical constituents interact) and others. The progress of research in chemical sciences has been phenomenal leading to emergence of many sub-disciplines such as material science, solid state and surface science, nanoscience and technology, chemical biology and others. We shall briefly review first the developments in chemical sciences research in the international scene.
The growth of research and development activities in chemical sciences has been spectacular in the last century compared to earlier centuries. With the advent of quantum mechanics, the nature bonding between different atoms in chemical compounds has been well understood. The knowledge of bonding coupled with the structural aspects (three dimensional disposition of different atoms in a chemical entity) provided the predictive ability of various properties of chemical compounds. The realization of the importance of structures of chemical entities resulted in the emergence of various spectroscopic techniques (infrared, Raman spectroscopy, nuclear magnetic and electron paramagnetic resonance, Mossbauer electron spectroscopics and others). The powerful techniques of observing atoms in molecules using scanning tunnelling and atomic force microscopy and scanning electron microscopy greatly aided the basic understanding of chemical systems particularly in material science and engineering, surface science, catalytic processes and others.
The newer demands on sophisticated techniques led to tremendous research input in the synthesis and reactivity of chemical compounds. Many notable accomplishments have been made especially in the last century. The most well-known and important among these are synthesis of Vitamin B12, chlorophyll, penicillin, taxol, epothilone palytoxin and others. The chemical ingenuity, skill and talents that went into the chemical synthesis of these complex systems led to the development of newer pharmaceuticals and drugs that are of direct relevance to human health. Various chemical processes using catalysts have been understood, particularly in petroleum industry. The petrochemicals and petroleum products specially polymers and plastics provided modern day materials that found extensive usage in our daily lives. The synthesis of complex systems is made possible by the discovery of many easy and elegant synthetic methodologies and reactions demonstrating the innovative skills of chemistry researchers. The complex systems of plant origin provided a great impetus to organic synthesis.
Another class of chemical compounds, metal-organic hybrid systems and metal oxides and mixed metal oxides, sulphides and chalcogenides constitute the area of solid state chemistry. One of the remarkable discoveries in this area is the demonstrated evidence of high temperature superconductivity in a mixed oxide system. Superconductors are those materials that offer no resistance to the passage of electric current. A few materials display the phenomenon only at very low temperatures, the difficulty being maintenance of these temperatures. It is highly desirable to have materials exhibiting superconductivity at moderately higher temperature to enable wider usage in a cost-effective manner. The material La(2-x)BaxCuO4, is the first compound that was shown to exhibit this phenomenon. These mixed metal oxide systems were first synthesized by C.N.R. Rao and his colleagues in India.
The discovery of a new form of carbon, fullerene (C60) in the early nineties spurred a great deal of research activities throughout the world scientific community. There are a host of carbon entities such as carbon nanotubes, carbon onions and others, which exhibit remarkable properties such as high tensile strength, catalysts, sensors and others. With the advent of these molecules, research in the synthesis of metal clusters consisting of a few atoms of metals, creation of nanosized (10-9 m) materials and a whole branch of nanoscience came into existence with potential applications in the development of molecular machines and others. There has been considerable progress in research in the molecular assemblage of chemical entities to desired dimensions and shapes to achieve some desirable properties. This gave rise to answers to important and fundamental questions like, how do molecules recognize one another, how do they bind, how to induce shape and size selective properties of molecules, how fast do they combine and how to control their movements. This is an interesting area of research pursuit in chemistry which has direct relevance to drug design, tailor made materials for specifically designed purposes, novel catalysts to improve the product design and rates of chemical processes, understanding of biological functions and others.
Along with these developments, there has been substantial contribution from theoretical chemistry which helped the progress of growth in research. Research chemists have been quick to recognize the importance of theoretical aspects that often add to predictive and understanding capabilities. Many different approaches such as density-functional methodology, Monte Carlo simulations, cluster model approach, quantum chemistry calculations, force-field approach and others have been developed to address problems such as role of solvents in fast reaction dynamics of chemical systems, molecular diffusion in different media, single molecule dynamics and others.
It is better now to review the research in chemical sciences in India and assess its strengths and weaknesses and also suggest approaches to enhance its vitality. The pioneering work by Acharya Prafulla Chandra Roy in the early 20th century in Kolkata was responsible for the great turn of events in chemistry in the Indian subcontinent. The discovery of a stable mercurous nitrite composed of two relatively unstable ions, unfolding of the interesting chemistry of hyponitrite ion, synthesis of a large number of organic sulphur compounds, coordination chemistry of heavy transition metal ions, iridium, platinum and gold are some of the notable contributions. In the subsequent decades, the major thrust in chemistry was in organic chemistry, especially in the chemistry of natural products. In recent years, efforts have been made in several new directions in the various branches of chemistry.
The chemistry of alkaloids, terpenes, flavones and steroids engaged the attention of Indian chemists in the earlier years. Synthetic drugs such as antimalarials, contraceptives, sulfinamides and sulfones received considerable attention. Synthesis of long chain fatty acids leading to partial synthesis of natural products was achieved. The pioneering contributions on flavones by T.R. Seshadri and his school of researchers have attracted international attention. Noteworthy work was carried out in the country on terpenes, especially those occurring in Indian plants. The work on Longifolene by Shuk Dev and his co-workers have led to the growth of perfumery industry in the country. Extensive investigations were made on natural colouring compounds related to benzopyrones and anthroquinones.
Work on synthetic dyes by K. Venkataraman and his group had a great impact on the textile industry. Several novel natural products characterized by unique carbocyclic skeletons and intricate stereochemical features have been synthesized. It is noteworthy to mention the isolation and detailed structural characterization of azadirachtin, a potent insect antifeedent compound and inhibitor of ecdysis, from the seeds of neem plant, Azadirachta indica by T.R. Govindachari and his co-workers has led to the revival of natural products chemistry in the country in recent years.
Research in natural products has assumed immense importance from the point of view of drug discovery and bioassay guided functionation of extracts to identify lead molecules. A coordinated activity in the area of drug discovery has been initiated by the Council of Scientific and Industrial Research in various laboratories and institutions.
Synthetic organic chemistry has been pursued by many researchers. Early work on the total synthesis of steroids and their derivatives by D.K. Banerjee and his research group laid the foundation for the growth of the pharmaceutical industry. Synthetic design of novel polyhydranes is a major area in which substantial achievements have been made. Synthetic work on the platonic hydrocarbon, dodecahydrane, attracted the attention of the international scientific community. A number of new reactions and organometallic reagents based on silicon, chromium, boron, palladium and phosphorus have been developed. One of the important aspects of research in organic chemistry has been the synthesis of several organic intermediates for the pharmaceutical industry in the country. This has directly benefited the industry; the speciality chemicals and pharmaceutical industries have registered an export market of US $3.5 billion accounting for 11% of the total exports from India.
Many important achievements have been made in the area of polymer chemistry. Synthesis of novel precursors for polymeric materials, polymer binders, hypergolic polymers and so on have been carried out. In addition to the synthesis of thermally stable polymers, several oligoesters were synthesized which when added to the plasticized PVC drastically reduced its inflammability. Research on speciality polymers with desired properties has been initiated in many laboratories.
The importance of interface areas between chemistry and biology has been recognized. Interesting work has been carried out by few groups in peptide chemistry and several peptides of biological interest have been synthesized. Isolation and characterization of myobacillin, a new polypeptide containing 13 amino acids was accomplished. Nucleic acid research initiated in a few laboratories essentially focused attention on the understanding of the functions of DNA at the molecular level and to generate nucleotides and novel reagents for site-specific modification of biomacro-molecules. Several studies have been initiated in the area of biomembranes and metal ion interaction with biomolecules.
Green chemistry has gained great importance today. Several research groups have taken up this challenge and are engaged in the synthesis of biologically active molecules. A large body of work has been generated in asymmetric synthesis in which a number of optically active naturally occurring terpenes and amino acids have been used as building blocks to get enantiomerically pure biologically active molecules.
Work in the emerging area of supramolecular chemistry, molecular recognition systems and design of multifunctional catalysts have become the focal point in some laboratories. The preparation of novel materials to perform specially designed functions has become a key feature. Significant advancements have been made in respect of non-linear optical materials and precursors of MOCVD.
In the area of analytical chemistry, solvent extraction, development of sophisticated electroanalytical methods, pollution abatement in industrial workers, and water clarification are some of the important subjects in which research has been pursued. Several laboratories/centres providing analytical facilities have been established in the country.
Research in inorganic chemistry in the country in the last few decades has been considerable. Noteworthy contributions have emerged in the areas of coordination chemistry, bioinorganic chemistry, organometallic chemistry, chemistry of main group elements, spectroscopy and structural inorganic chemistry. The directions of research have been on the synthesis of novel systems for studies on multiple bonded metal-metal clusters, stabilization of low and high valent transition metal ions, homogenous catalysis, metal ion binding in macro-cyclic and macrocyclic ligand systems bearing several donor atoms such as oxygen, nitrogen, sulphur, selenium, tellurium and others. The development of model systems for mimicking the active sites of metal-loenzymes and metal-loproteins, metal-nucleic acid interactions, photosynthetic functions are some of the fields in which notable progress has been made. These have a direct bearing on the role of metal ions in biology and medicine.
Considerable work has been carried out on organo tin and phosphorous compounds in view of their importance as insecticides and pesticides. Extensive work has been carried out on metal alkoxides which are precursors of novel ceramic materials.
Reaction mechanisms of both organic and inorganic systems have been pursued by several groups. Special mention should be made of the following: photochemical transformations, photoperoxidation, dimerization, quenching of fluorescence, emission spectroscopy of dyes, rare earth complexes, conversion of solar energy, laser spectroscopy, photo-isomerization, photocyclo-addition and others. Research centres are being established in different parts of the country for the investigation of laser spectroscopy and chemical dynamics for the understanding of ultrafast chemical processes.
The application of quantum mechanics to chemistry started in India around 1950. Theoretical methods are being widely used to understand the structures, stabilities and reactivities and organic inorganic molecules. New concepts, sophisticated formulations, mathematical theories (or models) in statistical and quantum mechanics, computational methods and strategies have been and are being developed for various static and dynamic properties of small and large systems both in ground and excited states. These include coupled cluster calculations, density functional methods, molecular modelling methods and theories of ultrafast processes. Apart from developing new concepts and methodology in theoretical chemistry, many notable contributions have been made on the applications of theory to the understanding of structure and reactivity in organic and inorganic systems.
At the chemistry/industry interface, electrochemical investigations include electrochemical energy systems, electrode kinetics, surface modified electrode systems, electroplating and corrosion problems, electro-chemical sensors, and work on solid catalysts as well as catalytic reactions have been carried out in several centres. The industrial applications have been pursued by many researchers in the country. The work on successful separation of isomers of petroleum products, particularly separation of isomers of aromatic hydrocarbons (e.g., xylenes) using zeolites has been one of the notable achievements in the country.
Research in solid state chemistry, surface science and materials chemistry are being actively pursued. In the last two to three decades, notable contributions have emerged in the study of phenomena structure-property relations and materials design. The materials include transition metal oxides, novel forms of carbon (fullerenes and carbon nanotubes), supramolecular assemblies, micro and macroporous solids, nanoparticles and thin films and clusters. The pioneering work of C.N.R. Rao and his colleagues in these areas received considerable appreciation in the international community. Special mention is made of the discovery of a simple method for fashioning aligned nanotube bundles and Y-junction nanotubes, which has received international acclaim in view of its application in electronic circuitry in the nanotechnology regime.
The various aspects of solid state chemistry investigated include superconductivity, porous solids, structural and electrical properties, colossal magnetoresistance, charge-ordering and related aspects, nano particles (nanotubes and nanowires), molecular solids and open frame work materials. Many interesting findings emanating from research in these areas have made a significant impact in the international scene. One of the most recent advances in nanotechnology is the lithography technique developed at the Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, using well characterized metal sols and other colloidal dispersions as inks for dipper raised patterns with narrow line being 20 nm (20 x 10-9m) wide. New facilities and centres to promote nano science and technology have been created.
A few areas of research that the country needs to focus on for a competitive edge in the international scene are listed here:
* Better materials for energy storage, alternative energy sources.
* Improved security in chemical production sites; practice of green chemistry in the laboratory and industry; substitution of less toxic chemicals in the manufacturing process, pollution prevention.
* Development of detectors/sensors for chemical (biological/radiological) materials.
* Better understanding of virus replication and better computer modelling for drug design.
* Chemistry applied to biology – develop systems that self-replicate and self-organize (neuro chemistry) understanding of the brain function – connection between chemistry and mind.
* Design of catalysts with predictable reactivity and generality – fuel cell catalysts.
* Designer material instead of bulk material – molecular electronics.
* Chemical reaction dynamics links to the understanding of complex systems.
Research in chemistry has been actively pursued in the country by a number of researchers in universities, national laboratories, other scientific establishments and R&D centres in a few industries. The major funding for research came from various governmental agencies. The number of people pursuing research in chemical sciences is quite considerable. Any rational assessment of the research output should involve consideration of the size of the community of researchers, the extent of financial inputs, the quality of education received by the researchers, the infrastructural facilities that exist, the incentives offered for better performance and the congenial scientific atmosphere offered by the institutions.
A detailed analysis of these aspects may not be necessary at this stage; however, it is easier to assess in term of output of research publications vis-a-vis the international scene. The number of research publications in chemical sciences in the last decade or so, has been on the decline. This demonstrates diminishing Indian presence in the international scene. The doctorates produced in the country in the area of chemical sciences have been stagnant or at best show a slight increase in number. This indicates that the research work carried out is not very competitive and lacks sophistication.
Before we analyze the options that are available to enhance the Indian presence in the international community of chemical science researchers, it is better to look into the problems that inhibit the growth of research in chemical sciences. The universities provide a major source of well-trained manpower for research and also been one of the major contributors to scientific research, especially in chemistry. In the last couple of decades, the pre-eminence of universities has been on the decline. The reasons are many but a few points are worthy of mention: (i) experimental and instrumental infrastructural facility in universities are inadequate, (ii) the quality of science education imparted has not been good, (iii) recruitment of faculty has been on the decline, (iv) lack of funding for research, and (v) rewards for better performance is non-existent.
Though there is an increase in the number of universities in the country, there is no adequate sustained financial support for science departments. The majority of researchers in chemical sciences come from a few central universities, IITs, IISc and CSIR laboratories. There is an immediate need to enhance the manpower in chemical science research.
There is an urgent need to improve science education in schools and universities incorporating the current trends in scientific knowledge. It is important to overhaul the existing education system by offering a four year Bachelor’s degree course in the sciences. This will assure good quality human capital willing to undertake research in many science disciplines. There must be an operational mechanism to recruit teachers on a continuous basis and ensure mobility of people from academia to industry and vice versa. This should provide an enabling environment for the awareness of the problem areas in research. There must be enhanced funding for research to sustain research outputs.
It is worthwhile to consider the creation of a centralized funding system such as the National Science Foundation – India and it should be institutionalized. This would relieve administrative interference, sub-critical funding and unnecessary controls to enable researchers to take up challenging problems. The new system should promote excellence in research by encouraging researchers to work in competitive areas. The chemical industry should invest part of their earnings in universities/institutions for the creation of centres of excellence in research. This will in due course enrich the university/industry interaction and provide industries the much needed knowledge capital.
