Dr. G. Vijay Nair F. A. Sc.
Senior Associate, JNCASR 
 NIST (formerly RRL), CSIR, Trivandrum, 695 019, INDIA
Tel. +91-471-490406 (O);  +91-471-358707 (R)
Fax: +91-471-491712
E-mail: vijaynair_2001@yahoo.com


 
 

 

 

Dr. G. Vijay Nair, born in October 1941 in Kerala, obtained B.Sc.(Chem) in 1960 from University of Kerala and Ph.D. from BHU, Varanasi (1967) and the University of British Columbia, USA (1965). He carried out the post-doctoral work with Josef Fried (Chicago), Peter Yates (Toronto) and Gilbert Stork (Columbia).

He started his career as Senior Research Chemist (1974) at the Lederle Laboratories of American Cyanamide Company and later became Principal Research Chemist (1987). He joined RRL-T as Deputy Director in 1990 and later became its Director (1997-2001). He has held several positions since 2001: Director-Grade Scientist in the Laboratory, CSIR Emeritus Scientist and currently a Senior Associate of JN  Center for Advanced Scientific Research. He is also a visiting professor at various universities. He has to his credit 190 publications being the senior author of a large number of publications in major international journals, 21 United States patents, many of which have world-wide coverage and guided 39 Ph.D. and 7 are currently being guided. Dr. Nair’s group works closely with industry. A collaborative project with American Cyanamid Company has been completed. Recently, a major collaborative project with Ranbaxy, funded by DST, aimed at the discovery of cholesterol lowering drugs has been completed. A project under Indo-French collaboration has been initiated.

He has been honoured with several awards, which include the Outstanding Scientist Award of Cyanamid Company (1981), INSA-DFG exchange fellowship to lecture in a number of Universities in Germany (1998), Invited Speaker at the 17th ICHC in Vienna in 1999, the MCR 2000, First International Conference on Multicomponent, Reactions, Munich, Germany, Oct. 2000, International Symposium in Munich, 18th International Conference on Heterocyclic Chemistry, Yokohama, Japan, July 29 – Aug.3, 2001 and Visiting Professorship at the University of Pernambuco in Brazil (May 2001), 11th IUPAC Symposium on Organometallic Chemistry directed towards Organic Synthesis (OMCOS11), Taipeh, Taiwan, July 22-27, 2001, Pfizer Symposium Speaker. I. I. Sc., Bangalore, 2002. Dr. Nair is a Fellow of the Indian Academy of Sciences and also Member of several Professional Organizations.

His research interests include cycloadditions, radical mediated C-C and C-heteroatom bond forming reactions, multicomponent reactions and heterocyclic synthesis in which his group has achieved international recognition in these areas.

During 1997-2001, as the Director of RRL-T, Dr. Nair has given vigorous leadership to the research programmes [applied, academic and societal] of the Laboratory. These include establishment of palm oil mills in Goa and Gujarat; fresh ginger extraction plant in Manipur; beneficiation flow charts for the clays of Gujarat; value addition to ilmenite through a new process for producing TiO2 slag and pig iron as well as high grade synthetic rutile from Kerala ilmenite using plasma, Development of a process for the preparation of eco-friendly multi-purpose catalyst based on aluminium silicate; Development of multi component reactions which offer prospect of creating libraries of heterocyclic components; Development of indigenous Al alloy castings for GSLV Cryogenic applications to replace Ti alloy castings; Design and implementation of pilot scale biofilters for odour control of ETP and Development of software package for casting simulation (Virtual Casting). Under Dr. Nair’s stewardship, the laboratory reached all time high using the following performance parameters: ECF, LR, total IF and average IF.

DESCRIPTION OF RESEARCH

During his tenure as Senior Research Chemist and later as Principal Research Chemist in the Medical Research Division of American Cyanamid Company Dr. Nair has made significant contributions in a number of areas of Medicinal Chemistry and Organic Synthesis. One facet of his work maybe singled out. His recognition that sulfated sugars exert powerful immunomodulatory action relevant to the treatment of autoimmune diseases such as arthritis led to the synthesis of a number of oligosaccharide poly (Hsulfates). Since the availability of oligosaccharides was extremely limited and the known synthetic methods primitive, new methods were developed for the efficient synthesis of oligosaccharides. One approach that was particularly fruitful involved the glycosylation of trityl ethers in a block condensation mode. A novel glycosidation of silyl ethers leading to a high yield synthesis of oligosaccharides and aryl glycosides was discovered in this context.

After his return to India towards the end of 1990, Dr. Nair has established a viable research group and has made noteworthy contributions in four major areas of organic synthesis viz.,

(i) Cycloadditions of o-quinones,

(ii) C-C bond forming reactions by oxidatively generated radicals

(iii) Asymmetric synthesis using chiral auxiliaries and

(iv) Heterocyclic synthesis using novel multicomponent reactions (MCRs)

Salient features of these studies are outlined in the following paragraphs:

CYCLOADDITIONS OF O-QUINONES

Cycloadditions, exemplified by the well-known Diels-Alder reaction, are among the most powerful ring forming reactions, and p-benzoquinone has served as excellent dienophile in such reactions. In contrast, however, the reactivity profile of o-quinones had received only scant attention. The recognition that o-quinones can potentially function as carbodienes, heterodienes and dienophiles prompted the RRL-T group to investigate their cycloaddition to a variety of substrates. Dr. Nair’s work has unravelled multiple modes of cycloaddition of o-quinones and much novel chemistry has emerged from this work. It was found that electron rich dienes undergo hetero Diels-Alder reaction with substituted o-benzoquinones to give benzodioxin adducts. It was established that the reaction proceeds by a two step mechanism; the initial [4+2] adduct is positioned for a [3,3] sigmatropic rearrangement leading to benzodioxins. Dr. Nair’s investigations have uncovered remarkable reactivity differences in the cycloaddition reaction of fulvenes with o-benzoquinones. 6, 6 dialkyl substituted fulvenes afforded the bicyclo[2.2.2]adducts with o-benzoquinones, whereas 6,6-tetramethylene fulvenes afforded a benzodioxin adduct suggesting a novel rearrangement of the fulvenes during the reaction . Other significant discoveries in the area include a facile synthesis of highly substituted benzene and indene derivatives, novel dipolar cycloadditions including the addition of carbonyl ylides, and a serendipitous synthesis of tropones by the Lewis acid catalyzed cycloaddition of acetylenes and o-quinones.

CARBON-CARBON BOND FORMING REACTIONS

One of the fundamental tasks in the synthesis of complex organic molecules is the construction of carbon-carbon bonds. A wide spectrum of synthetic methods involving ionic, pericyclic and radical reactions are available for carbon-carbon bond formation. Of these, synthetic organic chemists have made only limited use of free radical reactions until recently. Today, however the use of radicals in organic synthesis has increased dramatically and has grown in importance to the point where they are routinely considered in strategy level planning of complex targets. Radical reactions are accomplished using a variety of metal salts, of which Manganese(III) acetate and Cerium(IV) ammonium nitrate (CAN) have attracted considerable attention. In this context, investigations from the RRL–T group have unravelled a number of novel CAN mediated reactions of interest both from synthetic and mechanistic standpoints 7. Dr. Nair’s studies were initiated with the CAN mediated addition of dimedone to phenyl cyclohexene in methanol resulting in the corresponding dihydrofuran derivative in nearly quantitative yield, thus paving the way for a general synthesis of dihydrofurans 8,9. In the course of subsequent investigations, we have uncovered a novel dimerization of alkoxystyrenes in alcoholic solvents mediated by CAN. In acetonitrile as the reaction medium, styrenes underwent dimerization to afford a-aminotetralin derivatives which are analogous of the top selling antidepressant Sertraline. In contrast to the successful use of CAN in intermolecular reactions, the reagent has found practically little use in oxidative intramolecular annulations. Recent investigations in our laboratory have resulted in the stereoselective formation of 3,4-trans disubstituted tetrahydrofuran derivatives by the CAN mediated intramolecular cyclization of alkoxy cinnamyl ethers. It is conceivable that this methodology would find application in the synthesis of bioactive lignan derivatives Recently, there has been a flurry of activity towards developing newer methods for carbonheteroatom bond formation. Some of the results attesting the utility of CAN in carbonheteroatom bond formations, particularly, C-S, C-N, C-Se are the synthesis of azidocinnamates, azidostyrenes, dithiocyanates, diselenocyanates, vinyl sulfones, azidoiodides and vinyl bromides

ASYMMETRIC SYNTHESIS USING CHIRAL AUXILIARIES

The highlight of the work in asymmetric synthesis is the discovery of novel chiral auxiliaries derived from D-glucose. It has been shown that these auxiliaries are extremely useful in the synthesis of g-and d-lactones with high e.e values. This method appears suitable for the synthesis of a number of pheromones and other bioactive natural products.

HETEROCYCLIC SYNTHESIS USING NOVEL MULTICOMPONENT REACTIONS

Reactions of more than two starting materials are generally referred to as multicomponent reactions (MCRs). A number of advantages make MCRs attractive both in organic and combinatorial synthesis viz., simple procedures, facile execution, atom economy, convergence and ecofriendliness and they offer great promise in the synthesis of heterocycles. The renaissance of interest in multicomponent reactions has brought about a paradigm shift in organic synthesis in general and heterocyclic construction in particular18. In the context of Dr. Nair’s general interest in devising new methods for heterocyclic constructions, he has observed that 1:1 intermediates formed by the addition of isocyanides to dimethyl acetylene dicarboxylate (DMAD) react with electrophiles such as aldehydes and to sylimines, thus constituting novel MCRs19-23. Subsequently, it was shown that, similar 1:1 zwitterionic species could be generated by the addition of nucleophilic carbenes such as dimethoxycarbene and diaminocarbenes to DMAD24,25. The interception of these zwitterionic intermediates with various electrophiles such as aldehydes, ketones and dicarbonyl compounds afforded highly functionalized dihydrofuran and lactone derivatives26. It is interesting to note that dihydrofuran and lactone motifs are present in a number of biologically active natural products and other heterocyclic compounds. It is conceivable that the novel multicomponent reactions described herein will find application in the synthesis of a variety of heterocyclic compounds, and in natural product synthesis.

 

Honors and Awards

 

1.      CRSI- Silver Medal, 2006.

2.      Plenary Speaker, ACS-CSIR Symposium, OCCB-2006, NCL-Pune, January-2006.

3.      Plenary Speaker, International Symposium on Organic Chemistry (INSOC-2006), Kottayam, January-2006.

4.      Plenary Speaker, Southern Highlands Conference on Heterocyclic Chemistry, Moss Vale, Australia, September-2005.

5.      Visiting Professor, National Science Council, Republic of China, Taipei, April-2005.

6.      Professor Sukh Dev Endowment Lecture, NCL, Pune, April-2005.

7.      A. V. Rama Rao Foundation Lecture, JNCASR, Bangalore, March-2005.

8.      Invited speaker ICOS–15, International Conference on Organic Synthesis, August-2004, Nagoya, Japan.

9.      Invited speaker IUPAC-24th ISCNP Symposium, New Delhi, January-2004.

10.  Invited speaker NOST Symposium-Goa, November-2003.

11.  Invited speaker- INSA-KOSEF Symposium, Seoul, S. Korea, August-2003.

12.  Hon. Professor, Dept. of Environmental Science, Cochin University of Science and Technology, 2002-06.

13.  Invited speaker, 11th IUPAC Symposium on Organometallic Chemistry directed towards Organic Synthesis (OMCOS11), Taipei, Taiwan, July 22-27, 2001.

14.  Invited speaker, 18th International Conference on Heterocyclic Chemistry, Yokohama, Japan, July 29 – Aug.3, 2001.

15.  Visiting Professor, University of Pernambuco, Recife, Brazil (sponsored by Brazilian National Research Council), May 14-27, 2001.

16.  Invited Speaker, First International Conference on Multicomponent Reactions, Munich, Germany, October-2000.

17.  Fellow, Indian Academy of Sciences, 1999.

18.  Invited speaker, ISHC-17th International Conference on Heterocyclic Chemistry, Vienna, August-1999.

19.  INSA – DFG Visiting Scientist, Germany, 1998.

20.  Member, Editorial Board, Indian Journal of Chemistry, 1998-2004.

21.  Prof. Devaprabhakara Memorial Oration, I.I.Sc., Bangalore, India, 1998.

22.  Prof. R. H. Sahasrabudhey Lecture, University of Nagpur, 1989.

23.  Outstanding Scientist Award, American Cyanamid Co., 1981.

24.  Visiting Scientist, Columbia University, 1978-81.

 

 

 

 

 

Publications (1994-2007)

:

190

Patents

:

23

Ph. Ds supervised (Completed)

:

39

Ph. Ds  supervised (under completion)

:

7

 

Vijay Nair Research Group

 

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