摘要:

In Sweden and India— on green chemistry business I have been privileged to be involved in two significant green chemistry activities in the first two months of 2001. In February, the interviews were held for a new full Professorship in Green Chemistry at Chalmers University in Gothenburg in Sweden. This new Chair, which is possibly the first of its kind, is part of the Chalmers Environmental Initiative.The Initiative involves an investment of $11M in the area of environmental systems analysis with a total of seven new Professorships including others in Sustainable Energy Systems, Environmental Systems Technology and Management for Sustainability. Most of the new professors have now been appointed. They will greatly enhance the Chalmers Environment Network, which is closely linked to Swedish industry and the University of Gothenburg.It is especially appropriate that this should take place during the term of Sweden in the EU Presidency. We look forward to hearing of progress with this initiative and we hope that the new Professor of Green Chemistry will play a prominent role on the European and international stages. Earlier in the year in Delhi the First IUPAC International Symposium on Green Chemistry took place with over 220 delegates, including about 40 from outside India.It was very significant, given the increase in chemical manufacturing in the country to see how importantly the Indians regard this area. The inauguration ceremony was graced with the presence of the Chief Minister Mrs Sheila Dixit (requiring a huge security operation), who gave a speech to the conference on the positive and negative aspects of new technology.She concluded with a most appropriate quotation from the Father of her country, Mahatma Gandhi “There is enough for everybody’s need in this world, but not enough for everybody’s greed”. Among the other speeches that of the Vice-Chancellor of the University of Delhi, Professor Deepak Nayyar, was also memorable.He concluded that it is the interface of science and technology which needs to be developed for the world to become a greener place. There were many excellent presentations during the conference some of which illustrated the interdisciplinary nature of green chemistry especially at the chemistry–chemical engineering and biology–chemistry boundaries.However, I have to admit that it was not the high quality of the science or my first impressions of one of the world’s busiest cities that is likely to last longest in my memory—it was the interest of the ordinary staff in my hotel who quizzed me about the conference and the meaning of green chemistry. Readers will be pleased to hear that a complementary copy of this great journal now resides in the staff common room of one of India’s leading hotels! James Clark York, March 2001 Platform party at the IUPAC International Symposium on Green Chemistry in Delhi. Professor James Clark is in the centre, with Chief Minister Sheila Dixit on his right and Professor Pietro Tundo (University of Venice) on his left.This journal is © The Royal Society of Chemistry 2001 E D I T O R I A L G18 Green Chemistry April 2001 DOI: 10.1039/b102397gIn Sweden and India— on green chemistry business I have been privileged to be involved in two significant green chemistry activities in the first two months of 2001.In February, the interviews were held for a new full Professorship in Green Chemistry at Chalmers University in Gothenburg in Sweden.This new Chair, which is possibly the first of its kind, is part of the Chalmers Environmental Initiative. The Initiative involves an investment of $11M in the area of environmental systems analysis with a total of seven new Professorships including others in Sustainable Energy Systems, Environmental Systems Technology and Management for Sustainability. Most of the new professors have now been appointed.They will greatly enhance the Chalmers Environment Network, which is closely linked to Swedish industry and the University of Gothenburg. It is especially appropriate that this should take place during the term of Sweden in the EU Presidency. We look forward to hearing of progress with this initiative and we hope that the new Professor of Green Chemistry will play a prominent role on the European and international stages.Earlier in the year in Delhi the First IUPAC International Symposium on Green Chemistry took place with over 220 delegates, including about 40 from outside India. It was very significant, given the increase in chemical manufacturing in the country to see how importantly the Indians regard this area. The inauguration ceremony was graced with the presence of the Chief Minister Mrs Sheila Dixit (requiring a huge security operation), who gave a speech to the conference on the positive and negative aspects of new technology.She concluded with a most appropriate quotation from the Father of her country, Mahatma Gandhi “There is enough for everybody’s need in this world, but not enough for everybody’s greed”.Among the other speeches that of the Vice-Chancellor of the University of Delhi, Professor Deepak Nayyar, was also memorable. He concluded that it is the interface of science and technology which needs to be developed for the world to become a greener place. There were many excellent presentations during the conference some of which illustrated the interdisciplinary nature of green chemistry especially at the chemistry–chemical engineering and biology–chemistry boundaries.However, I have to admit that it was not the high quality of the science or my first impressions of one of the world’s busiest cities that is likely to last longest in my memory—it was the interest of the ordinary staff in my hotel who quizzed me about the conference and the meaning of green chemistry. Readers will be pleased to hear that a complementary copy of this great journal now resides in the staff common room of one of India’s leading hotels! James Clark York, March 2001 Platform party at the IUPAC International Symposium on Green Chemistry in Delhi. Professor James Clark is in the centre, with Chief Minister Sheila Dixit on his right and Professor Pietro Tundo (University of Venice) on his left. This journal is © The Royal Society of Chemistry 2001 E D I T O R I A L G18 Green Chemistry April 2001 DOI: 10.1039/b102397g

ISSN:1463-9262    

DOI:10.1039/b102397g

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

Highlights Duncan Macquarrie reviews the latest research in green chemistry Oxidations A team led by Craig Hill, from Emory University, Atlanta, has succeeded in using a diversity-based approach to develop a new highly efficient and selective oxidation catalyst for the oxidation of sulfides to sulfoxides (J. Am. Chem. Soc., 2001, 123, 1625). They combined various redox-active cations with a range of (mostly polyoxometallate) anions, and came up with a catalyst derived from the reaction of a gold and a silver species.The product of this reaction was found to oxidize sulfides to the corresponding sulfoxide with excellent efficiency under very mild conditions, being more active than any other known catalyst for this transformation. The oxidation used oxygen as primary oxidant, and turnover numbers reached 200.A further oxygen-based oxidation has been reported by B. M. Choudhary of the Indian Institute of Chemical Technology in Hyderabad (Angew. Chem., Int. Ed., 2001, 40, 763). They used a nickel–aluminium hydrotalcite as a catalyst for the aerobic oxidation of alcohols to aldehydes and ketones. In particular, they found that the system was excellent for the oxidation of a-ketols to a-diketones, as well as for vicinal diols to the corresponding diketones.Yields were high in the optimum solvents (hydrocarbons such as cyclohexane or toluene) after 6 h at temperatures below 100 °C. Reuse was also demonstrated. Diols from osmium tetroxide The formation of diols from osmium tetroxide remains a thorny challenge. The reagent gives unparalleled activity, but is both highly toxic and volatile, making it unsuitable for use. Attempts to immobilise it, for example, on polyvinylpyridine have failed, since the coordinative link to the backbone must be broken for the reaction to proceed.The group led by Pierre Jacobs of the Catholic Univerity of Leuven, Heverlee, Belgium, have now provided an elegant method for the immobilisation of osmium tetroxide, leading to a stable, immobilised reagent (Angew.Chem., Int. Ed., 2001, 40, 586). Their approach relies on the ability of osmium tetroxide to form a stable osmate ester by coordination with a silica-supported tetrasubstituted double bond. This material can then form an osmate with a second molecule of alkene. This di-alkene complex then undergoes selective hydrolysis to form the product diol and regenerate the starting complex.Leaching studies indicated that no dihydroxylation occurred after removal of the solid catalyst, unlike that observed with polyvinylpyridine complexes. Epoxidation Thomas Maschmeyer’s group at the University of Delft, The Netherlands, have published details of a rapid screening study aimed at the preparation of titanium silsesquioxane catalysts for epoxidation (Angew.Chem., Int. Ed., 2001, 40, 740). They investigated methods to speed up and simplify the synthesis of these interesting materials, and found several improvements to the conventional method, making synthesis faster and cheaper. Catalytic activity was also found to be dependent on the conditions of synthesis.While the best catalytic activities were not better than those previously reported, the improvements in the synthetic methodology should allow access to these catalysts in a cleaner manner. Spinning disk reactors Alternative reactor design is one method which can have an enormous impact on a process, both from the point of view of optimising the performance of the reaction and from simpler isolation.Norman Lewis and his collaborators at SmithKline Beecham and Newcastle University, UK, have published details of an evaluation of a spinning disc reactor in the synthesis of a pharmaceutical intermediate and in the crystallisation of an active pharmaceutical (Org. Proc. R+D, 2001, 5, 65). They found that the phase transfer-catalysed Darzens reaction proceeded very well in such a reactor, giving high yields and throughput, with significantly reduced impurity levels. Throughput for a 15-cm disc was estimated to be 8 tonnes p.a. In a second application, crystallisation of a salt was shown to be successful too with good control over particle size. This journal is © The Royal Society of Chemistry 2001 NEWS & V I E W S DOI: 10.1039/b102398p Green Chemistry April 2001 G19

ISSN:1463-9262    

DOI:10.1039/b102398p

出版商:RSC    

年代:2001

数据来源: RSC

摘要:

Highlights Duncan Macquarrie reviews the latest research in green chemistry Oxidations A team led by Craig Hill, from Emory University, Atlanta, has succeeded in using a diversity-based approach to develop a new highly efficient and selective oxidation catalyst for the oxidation of sulfides to sulfoxides (J. Am. Chem. Soc., 2001, 123, 1625). They combined various redox-active cations with a range of (mostly polyoxometallate) anions, and came up with a catalyst derived from the reaction of a gold and a silver species.The product of this reaction was found to oxidize sulfides to the corresponding sulfoxide with excellent efficiency under very mild conditions, being more active than any other known catalyst for this transformation. The oxidation used oxygen as primary oxidant, and turnover numbers reached 200.A further oxygen-based oxidation has been reported by B. M. Choudhary of the Indian Institute of Chemical Technology in Hyderabad (Angew. Chem., Int. Ed., 2001, 40, 763). They used a nickel–aluminium hydrotalcite as a catalyst for the aerobic oxidation of alcohols to aldehydes and ketones. In particular, they found that the system was excellent for the oxidation of a-ketols to a-diketones, as well as for vicinal diols to the corresponding diketones.Yields were high in the optimum solvents (hydrocarbons such as cyclohexane or toluene) after 6 h at temperatures below 100 °C. Reuse was also demonstrated. Diols from osmium tetroxide The formation of diols from osmium tetroxide remains a thorny challenge. The reagent gives unparalleled activity, but is both highly toxic and volatile, making it unsuitable for use. Attempts to immobilise it, for example, on polyvinylpyridine have failed, since the coordinative link to the backbone must be broken for the reaction to proceed.The group led by Pierre Jacobs of the Catholic Univerity of Leuven, Heverlee, Belgium, have now provided an elegant method for the immobilisation of osmium tetroxide, leading to a stable, immobilised reagent (Angew.Chem., Int. Ed., 2001, 40, 586). Their approach relies on the ability of osmium tetroxide to form a stable osmate ester by coordination with a silica-supported tetrasubstituted double bond. This material can then form an osmate with a second molecule of alkene. This di-alkene complex then undergoes selective hydrolysis to form the product diol and regenerate the starting complex.Leaching studies indicated that no dihydroxylation occurred after removal of the solid catalyst, unlike that observed with polyvinylpyridine complexes. Epoxidation Thomas Maschmeyer’s group at the University of Delft, The Netherlands, have published details of a rapid screening study aimed at the preparation of titanium silsesquioxane catalysts for epoxidation (Angew.Chem., Int. Ed., 2001, 40, 740). They investigated methods to speed up and simplify the synthesis of these interesting materials, and found several improvements to the conventional method, making synthesis faster and cheaper. Catalytic activity was also found to be dependent on the conditions of synthesis.While the best catalytic activities were not better than those previously reported, the improvements in the synthetic methodology should allow access to these catalysts in a cleaner manner. Spinning disk reactors Alternative reactor design is one method which can have an enormous impact on a process, both from the point of view of optimising the performance of the reaction and from simpler isolation.Norman Lewis and his collaborators at SmithKline Beecham and Newcastle University, UK, have published details of an evaluation of a spinning disc reactor in the synthesis of a pharmaceutical intermediate and in the crystallisation of an active pharmaceutical (Org. Proc. R+D, 2001, 5, 65). They found that the phase transfer-catalysed Darzens reaction proceeded very well in such a reactor, giving high yields and throughput, with significantly reduced impurity levels. Throughput for a 15-cm disc was estimated to be 8 tonnes p.a. In a second application, crystallisation of a salt was shown to be successful too with good control over particle size. This journal is © The Royal Society of Chemistry 2001 NEWS & V I E W S DOI: 10.1039/b102398p Green Chemistry April 2001 G19

ISSN:1463-9262    

DOI:10.1039/b102113n

出版商:RSC    

年代:2001

数据来源: RSC