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Currently, Organic Chemistry and Environmental Chemistry are Dr. Apurba Bhattacharya's main research focus.
His research is directed mainly towards the following two areas of chemistry:
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Dr. Apu's students are generally expected to do well in the class room as well as excel in the laboratory by performing various multiple reactions. |
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Process chemistry, the practice of scaling up chemical production from gram and kilograms to thousands of gallons while always of vital importance, has lately become a highly visible enterprise in the pharmaceutical sector. In the pharmaceutical industry, once the medicinal chemist defines the target molecule, the process chemist finds the most efficient, economical and safe route to make the molecule and its analogues. We have established collaborative programs with several leading pharmaceutical companies (e.g. Bristol-Myers Squibb Pharmaceuticals Research Institute, and Dannier Chemical, Inc.[please view their NEWS link]) whereby the research students will be involved in identifying and solving process related problems and issues of potential mutual
interest. This involves synthesizing initial quantities of drug candidates using the
existing-route as well as improving the existing synthesis, possibly following a
completely different strategy from the medicinal route so that it can be scaled up for
commercial production.
This is a win-win situation for both academia and industry. It gives our research students valuable exposure to industrial problems and the training involved in solving those problems, which will help them immensely when they enter the job market.
Over the past few years significant amount of research activities in the chemical community have been directed towards the development of new technologies and methodologies for environmentally benign processes. This area of chemistry has received extensive attention and is often referred to as "green chemistry". "Green chemistry" focuses on the design, manufacture, and use of chemicals and processes that have little or no pollution potential or environmental risk and are both economically and technologically feasible. The principle of green chemistry can be applied to broad areas of chemistry including synthesis, catalysis, reaction conditions, separations, analysis and monitoring. Green Chemistry differs from conventional chemistry in several different categories including nature of starting materials, reagents, reaction conditions and target molecule.
1. Solvent Minimization. Most organic reactions are performed in presence of organic solvents. A reaction, which is performed without addition of any solvent, has several advantages. The cost of processing (adding the solvent and its subsequent removal), handling and disposal of the solvent is completely eliminated. Performing the reaction neat without any solvent also results in significant improvement in throughput or process efficiency. 2. Reactions on Solid Support; Waste-free Catalytic Technology. A number of chemical processes use either stoichiometric acidic or basic conditions resulting in the production of stoichiometric amount of waste salt. Importantly, inorganic salts account for the bulk of industrial chemical waste. Besides polluting soil and ground water, salts can lower the pH of atmospheric moisture and have been implicated in the formation of acid-dew. Designing chemical processes which utilizes only catalytic amount of acid/base (via regeneration of the catalyst) or enables separation of the catalyst by simple filtration and reuse would minimize waste formation.
4. Atom Economy. This concept was elucidated and demonstrated by Trost. The improvement of synthetic efficiency requires the development of more reactions wherein the product is the sum of the reactants with anything else being required only catalytically, namely, atom economic processes. 5. Energy Conservation: Application of Microwave and Sonication in Organic Synthesis. Significant acceleration of organic reactions can be achieved by the use of both microwave as well as ultlasonication technology. In order for these processes to be practical the reaction units have to be engineered to operate reliably and safely on a routine basis preferably in a continuous or semi-continuous mode. 6. Chiral Phase-Transfer Catalysis. Catalytic asymmetric synthesis with high enantioselectivity and nearly quantitative chemical yield via chiral phase-transfer catalysis (PTC) will be applied to the synthesis of pharmaceuticals. The chiral PTC technology offers potential as a pseudo-enzymic process in organic synthesis in terms of simplicity, ease of operation, and enantiospecificity. Mechanistic studies involving the catalyst-substrate interactions include the importance of donor-acceptor interactions and electronic complimentariy for chiral recognition.
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Chemistry Home | Information | Academics | Faculty | Research |
Pharmaceutical Process Research and
Development.
Environmentally
Benign Processes in Organic Synthesis.
The scope of
Research and Development in this area is enormous. We intend to concentrate on the
following specific areas of chemistry.
3. Organic
Reactions in Water. Recently there has been increasing interest in the use of
water as a medium for organic applications. Utilizing of water as reaction medium for
organic substrate would minimize the formation of enormous amounts of organic waste. Even
simple organic reactions (e.g. Diels Alder reactions, Claisen rearrangements and
nucleophilic additions) in water solutions can show hydrophobic effects on rates and
selectivity’s if nonpolar segments of the reactants are brought together in the TS.