30 No. 6
IUPAC —Then and Now: Reflections on 40 Years of Involvement
by Jeffery Leigh
Many people have asked me what I actually have done during my time of involvement with IUPAC, which is now approaching 40 years, especially since a yearly trip to whatever exotic spot has been chosen for a meeting is no longer seen as being much of a perk. Others want to know what the organization does. That, at least, is easy to answer. IUPAC’s mission, the reason for its existence, is to enable chemists to communicate unequivocally and without misunderstanding, and in particular to be sure that different authorities do not start arguing at cross purposes because they are not sure that the subject of their discussion is understood by both parties to be the same substance. Regulatory authorities, publishers, and researchers are aware of this problem and ask for an independent authority to advise them on such matters. That authority is IUPAC.
One of IUPAC’s most important tasks is to develop a universal systematic nomenclature for chemical compounds. This was what first attracted me to IUPAC. I started by being intrigued by a kind of cross-word approach to nomenclature: Could you define a name by a set of rules that would always allow anyone to infer the chemical structure from it? This was before the routine availability of computers, which have changed the way in which chemical information is stored and manipulated.
Another aspect of IUPAC’s work involves standardization. For example, estimates of atomic weights are still being made, and though changes in established values are small, they are important in some circumstances. IUPAC continuously assesses the new literature and amends the list of atomic weights every two years. Isotopic abundances for a given element are not independent of source, as was once believed, and they vary from place to place and from heavenly body to heavenly body. IUPAC also reviews new data in this area.
IUPAC advises chemists on how to assess statistical data, on how to present analytical results, and on how to teach chemistry, particularly in emerging regions with limited resources, by providing teaching aids and advice, and organizing conferences. IUPAC publishes the results of its deliberations in its scientific journal Pure and Applied Chemistry and a variety of references listed below.
|I started by being intrigued by a kind of cross-word approach to nomenclature: Could you define a name by a set of rules that would always allow anyone to infer the chemical structure from it?
IUPAC sponsors conferences, and one condition for IUPAC sponsorship is that the government of the host country will issue visas to bona fide scientists who wish to attend, no matter from which country they come. This was particularly important during the Cold War and is still necessary in some regions such as the Middle East. Finally, IUPAC encourages interaction between industry and academia, considering and publicizing the value and the dangers of chemistry for the world as a whole.
One of IUPAC’s most contentious functions, carried out jointly with IUPAP, its sibling physics organization, is to assess researchers’ claims to have synthesized a new element, and adjudicate on priority. Only when this has been done are the discoverers invited to suggest a permanent trivial name. Most go for famous compatriots or home towns and states. Thus, we now use names such as seaborgium, hassium, dubnium, and californium. In the meantime, IUPAC has devised the peculiar three-letter symbols and related names for elements that are yet to be prepared beyond all reasonable doubt, but which are discussed in the literature. The element of atomic number 111 was provisionally called unununium, symbol Uuu, until recently, when IUPAC decided that it had been synthesized unequivocally by researchers in Germany, who have now given it the permanent name roentgenium, with the symbol Rg. This name is to honor the German discoverer of X-rays, Wilhelm Roentgen. Evidence for the element 112, Uub, ununbium, is currently being assessed. When the Dubna and Berkeley laboratories were competing in a race to establish new elements in the 1980s, there were some unpleasant and difficult political pressures applied to the chairmen of the commissions. To their credit, all parties finally accepted the IUPAC decisions.
|. . . it was always necessary to reach the conclusion that the chairman wanted, and on many occasions we worked from nine till nine, when the exhausted and hungry members of the commission finally capitulated.
The activities mentioned above have always been principal aims of IUPAC, but how the Union approaches them has changed significantly since I first became involved. I attended my first meeting, which was of the Commission on Nomenclature of Inorganic Chemistry (CNIC), as a stand-in because they could find no one to act as meeting secretary. My boss at work was Joseph Chatt, a long-time IUPAC enthusiast. At home, we subordinates were frustrated by his insistence that we use correct IUPAC nomenclature, which we didn’t appreciate or understand. It was a laboratory joke that everything in a written report had to be presented with a plethora of square brackets in order to satisfy Joseph. He would disappear from the country annually for mysterious IUPAC meetings, but eventually he asked me if I were prepared to come to Munich to act as secretary for this one meeting of CNIC. As I had worked in Munich with E.O. Fischer, and was very fond of the city, I was delighted to do so. This was in 1973, and I have been a member of IUPAC in one capacity or another ever since.
Most of the archives were carried about in Mo’s head.
When I first became involved in IUPAC, the secretariat was run by Mo (Maurice) Williams and his devoted assistant Ann Troughton. The office was housed in a small shopping mall on the outskirts of Oxford. Chatt relied on the IUPAC office for considerable help, even in arranging his journeys to meetings. Mo also seems to have been a part-time travel agent. Certainly he and Ann were the most permanent aspect of the administration of the Union. Most of the archives were carried about in Mo’s head. Members of the commissions did not worry much about finance since Mo handled everything. Nowadays, the permanent staff occupies a small office with five employees in North Carolina and an even smaller office with one proud independent employee in Boston, both in the United States. Everything is much more professional, but, unavoidably, less personal. The use of e-mail rather than the telephone, more efficient but requiring much less human interaction, has undoubtedly caused this to happen.
|CNIC meeting in 1978 (from left): F. Bertello (Argentina), C.K. Buschbeck (Federal Republic of Germany), D.M.P. Mingos (UK), B.F. Myasoedov (USSR), Y. Jeannin (France), W.H. Powell (USA), J. Chatt (UK), K. Yamasaki (Japan), and G.J. Leigh (UK).
A main characteristic of CNIC (and of its sister Commission on Nomenclature of Organic Chemistry, CNOC) at that time was its iron-willed chairman. It became evident to me that CNIC had no defined program apart from the plans of the chairman. Most of the members of CNIC and CNOC had been in their posts for many years, and they knew the published inorganic nomenclature rules and IUPAC rules intimately. IUPAC reference books are continually revised but subsequent editions retain the cover color of the first version, so organic nomenclature is always found in the Blue Book, and inorganic in the Red Book, whatever the editions, and so on. The first version of the inorganic rules (Report of the Committee for the Reform of Inorganic Chemical Nomenclature) was actually written in German and had been completed just before the Second World War. An English translation was published in 1940. The first Red Book version was published in 1957 and had parallel texts in English and French. For most of the members of CNIC at that time, that publication was regarded as finished, but regular meetings of IUPAC still provided a good opportunity to see old friends, argue about angels and points of needles, and to gain prestige at home, if any of your colleagues actually knew what IUPAC was supposed to be. The agenda of a meeting was drawn up at the beginning of the first day, and was worked through solidly. However, it was always necessary to reach the conclusion that the chairman wanted, and on many occasions we worked from nine till nine, when the exhausted and hungry members of the commission finally capitulated. After dinner, however late, the secretary had to write the minutes for approval the following morning! When the CNIC meeting coincided with the General Assembly, the chairman would suddenly announce that he had to go to another meeting, and depart with a throw-away line such as: “It’s up to you to decide this matter without me.” In truth, it never was, unless the decision was what the chairman actually wanted.
CNOC worked rather similarly, but we did try to hold joint meetings of CNIC and CNOC, because overlaps of nomenclature were becoming evident, with the development of areas such as organometallic chemistry. These meetings were often a dialogue of the deaf. Both commissions knew how to name the compounds that fell within what they regarded as their aegis, and no quarter was asked or given. CNOC also had the benefit of a long established and widely accepted methodology, whereas CNIC were relative ingénues. So we ran along parallel lines, due to meet only at infinity, and few of us were likely to survive long enough to see that happy event. Evidently things had to change, and with the proper application of rules concerning terms of membership things eventually did. Newer and younger people arrived in CNIC and proper programs of work were established by the 1980s. The next version of the Red Book was published in 1990.
Many of the difficulties described here have now faded away. Both CNIC and CNOC have been abolished. The Chemical Nomenclature and Structure Representation Division (Division VIII) is formally responsible for what they once did. This is clearly sensible, because nomenclature is now treated as a single subject. However, I remain to be convinced that the current project system will suffice to deal with long-term activities such as regular revision of the Red and Blue Books. There are relatively few nomenclaturists of either stripe on the division committee, and many nomenclature activities require large groups of workers. The projects may have to be very flexible to accommodate them. Indeed, recommended atomic weights are revised by what seems to me to be a permanent commission under another name, and quite justifiably so.
In nomenclature, some new activities are proceeding under the aegis of Division VIII. There is a project to identify Preferred IUPAC Names, or PINs, which will be the names used in legal documents. Currently, IUPAC nomenclature procedures can lead to more than one name for a given compound, in order to select one name. New IUPAC documents will carry the PINs of the compounds they describe. Since IUPAC cannot impose its suggestions on the chemistry community, and because chemists will continue to read the older literature with its multiplicity of names, IUPAC will continue to cite these other names alongside the PINs.
Many systematic names are very long and difficult to construct accurately for any but a skilled nomenclaturist. A particularly innovative development has been to construct a language that can enable a computer to draw a chemical structure by having it read what, to the eye, is simply a meaningless string of alphanumeric symbols, or to construct such a string when it is presented with a structure written in a particular manner. Such a string is termed an International Chemical Identifier, or InChI (pronounced “inchee”). An InChI is unique to any given compound and provides an unequivocal method for describing its structure.
There seems to me to be two major internal problems for IUPAC to solve in order for the organization to remain in good health. It is vital to attract newer and younger people to take part in IUPAC’s activities, and not just senior persons who have reached a certain degree of eminence in their home organizations. However, motivations such as my own original stimulus are no longer enough, because the activities of IUPAC, however vital, do not carry enough prestige to persuade a person embarking on an academic career to spend time on activities that do not result in research publications. We need more input from National Adhering Organizations (NAOs) and more prestige to attach to IUPAC activities. There are currently 51 NAOs, each paying a subscription based upon the annual turnover of its chemical industry. This money is used to run the Union. The individual members of IUPAC, now as in the 1960s, are usually nominated by their own NAOs, and are volunteers whose time devoted to IUPAC work is limited by their other professional responsibilities. We need the NAOs to publicize IUPAC’s work and to try to ensure that such work is recognized by national authorities as useful and valuable.
The other problem is to ensure that there is a steady supply of projects that are of value and use to the community. Many of the current projects stem from older persons and older programs, but a stream of suggestions arising from outside the Union would be invaluable. A campaign by individual NAOs amongst their own members might be one way to approach this. At the least it would publicize IUPAC activities in the community at large.
IUPAC Reference Publications
The most important IUPAC reference publications are listed below.
- Compendium of Analytical Nomenclature (definitive rules 1997), 3rd edition, 1998, known as the IUPAC Orange Book.
- Quantities, Units and Symbols in Physical Chemistry, 3rd edition, 2007, known as the IUPAC Green Book.
- Combining and Reporting Analytical Results, 2006.
- Compendium of Chemical Terminology, 2006, known as the IUPAC Gold Book.
- Nomenclature of Inorganic Chemistry, IUPAC Recommendations 2005, known as the IUPAC Red Book.
- Compendium of Terminology and Nomenclature of Properties in Clinical Laboratory Sciences, 1995, known as the IUPAC Silver Book.
- Multilingual Dictionary of Analytical Terms, 1994.
- The Nomenclature of Organic Chemistry, 1993, known as the IUPAC Blue Book (a new edition is in preparation).
- A Guide to IUPAC Nomenclature of Organic Compounds (recommendations 1993), A Guide to the Blue Book, 1993.
- Compendium of Macromolecular Nomenclature, 1991, known as the IUPAC Purple Book (a new edition is in preparation).
For those whose principal interest is nomenclature, there are elementary guides available, suitable for teachers and students rather than for specialists. One of the most important is Principles of Chemical Nomenclature: A Guide to IUPAC Recommendations, 1998. The writer is currently leading a project to revise this text, and it is hoped that a newer version will appear before the end of 2009.
Jeffery Leigh <[email protected]> is a member of the Chemical Nomenclature and Structure Representation Division (IUPAC Division VIII). He is an emeritus professor of Environmental Science at the University of Sussex.
last modified 7 November 2008.
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