Orchin, Milton - Component of : Early Ideas in the History of Quantum Chemistry.

Teaching : A Lifetime of Learning

Milton Orchin

Birthday Celebration, December 10, 1999

Introduction to this document, taken from

Newsletter Dept. Chem. Cincinnati

From The Editor
{John. S. Thayer, Ph.D., website note}

On December 10, 1999, the Chemistry Department held the "85.5th Birthday Party" in honor of Professor Milton Orchin. For those of us privileged to attend, this was an unforgettable experience.

One highlight was Professor Orchin‘s address Teaching: A Lifetime of Learning , which we are proud to reproduce, slightly edited, in this special tribute issue. At that party, a memorial booklet entitled What a Privilege! was issued to the attendees. Some copies of this booklet, which commemorates Professor Orchin‘s career, are still available; if you would like a copy, please send a note or FAX :Please address all correspondence to here.

Among Professor Orchin‘s many accomplishments was the establishment of the Departmental Newsletter, now known as CHEM BOND.
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We wish to express our sincere and deepfelt thanks to Kim Carey {Editorial Assistant, website note} for the time and effort she has put in, both on the birthday party and on this special issue.

News Flash :

We have just {Fall 2000, website note} learned that Professor Orchin has been included in the recent book Candid Science written by Istvan Hargittai (Editor of the journal Chemical Intelligencer). Only thirty-six chemists from around the world have been included, and these include eighteen Nobel Laureates!

In Professor Orchin‘s own words, "I feel pretty humbled to be included in the prestigious 36. lt is the most important recognition that I have ever received, and I owe a lot to the University of Cincinnati and the Department of Chemistry for the opportunities which made this recognition possible."

I want to thank all of you for being here and especial thanks to those of you who have traveled from cities around the country to share with me and the Department of Chemistry what is for me and my loved ones a memorable occasion.

This is, as you know, a kind of birthday celebration. Although I won‘t dwell on the significance and good fortune of exceeding the biblical lifetime span of three score and ten, I never thought reaching 85 would be something that I would personally experience but rather something that I would read about others experiencing.

For those of you who have never met my immediate family and for those of you who have and wish to revive memories of them I would like to introduce them now starting with my youngest son ...
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I did my undergraduate studies at OSU in Columbus.
I didn‘t have a problem agonizing over school choice because the in-state tuition for a full year there at that time was $60.00. For me OSU was ideal. It was a big school with many distinguished faculty and I liked the anonymity.

I appreciated the quarter system, for it allowed a large choice of subjects outside the major. I was unbelievably fortunate in selecting Mel Newman as my graduate school mentor, and lucky to spend my first year of graduate studies working in the intimacy of the small laboratory I shared with him as his first graduate student. As many of you know, he was a master of laboratory techniques. He taught me what it means to be efficient in the lab; not to do anything more than was necessary but to take great care and patience with what could be significant. His publications reflected bis thinking: “Get to the point and eliminate every unnecessary word!“ His enthusiasm was contagious and he instilled in me a lifetime love of chemistry. When I think of Mel‘s influence I am reminded of an admonition that Albert Einstein gave: “Everything should be made as simple as possible but not simpler‘.

For ten years prior to corning to the University of Cincinnati, I worked at the U.S. Bureau of Mines in the Synthetic Fuels Division. The major goal of this work was to promote the commercialization of processes which convert coal (a solid fuel) to a liquid transportation fuel resembling petroleum. And in studying various aspects of coal chemistry, I began to understand the importance of catalysis and developed a life-time interest in the subject. One ofthe aspects of catalysis that has always appealed to me is that it is a way to save time. Time is, as it should be, the most precious human possession. Time is what is important to us all, because we know our own time is limited and we strive to make the most of what is dealt to us. The ultimate goal of catalysis is to make desirable things in a shorter period of tirne and with less expenditure of energy.

In mulling over what I wished to say this evening I decided to discuss two examples, each of which exemplifies how much I have learned from students. These examples were selected in part because they involve four or five former students, none of whom are present tonight. This allows me to tell their story without fear of contradiction. and their absence provides me with a criterion to avoid the anguish of selection from those other of my students who are indeed present and would merit mention. One example deals with laboratory research, and the second involves a teaching experience.

The first story concerns my very first doctoral student, J.D. Fitzpatrick. The first thing to mention about Fitz was that he was older than I! I subsequently found it not uncommon that students were smarter than I, but older, no. Fitz had an undergraduate degree in chemical engineering and had been working for Emery Industries for about 15-20 years when he decided he wanted to go back to school and get a Ph.D. in chemistry. He talked Emery Industries into cooperating with him in this effort; after thinking about what Fitz would work on I suggested he study the relative rates of oxidation of some fatty acids. Emery Industries, here in Cincinnati was one of world‘s most important producers of fatty acids; one of their worries about the use of fatty acids was that they slowly went rancid due to reaction with air. In particular I suggested we look at the nature of the reaction of oleic acid with oxygen.

Now oleic acid is a long straight chain of carbon atoms terminated by a carboxyl group, right in the middle of the chain is a double bond which makes it a mono-unsaturated acid. The two halves of the chain in oleic acid are on the same side of this double bond. Such an arrangement is called a cis form.

When the two halves of the chain are on opposite sides of the double bond they are said to be in the trans configuration, and this isomer of oleic acid is called elaidic acid. Fitz was going to prepare each of these two acids and study the difference in rate of reaction with oxygen between these isomeric cis and trans fatty acids. As most of you know, the trans acids are higher melting than the cis acids; In the 1950‘s producers wanted high melting fatty acids as cooking oils, and so there were standard methods for converting a cis acid like oleic, which is an oil at room temperature, to its isomer, elaidic acid which is a solid at room temperature. Today the objectives are just reversed and we are advised to avoid trans fatty acids. And so Fitz started to prepare pure oleic acid. He bought a gallon of olive oil, virgin olive oil, which is the best source of oleic acid. “Why virgin olive oil?“ I asked. He explained that the oil from olives that had been pressed only once was called virgin olive oil. Calling something that had been pressed only once, virgin, seemed like a mis-use of the word but I wasn‘t about to take on the fatty acid industry.

Well after several weeks of work Fitz had about a liter of very pure oleic acid. We figured the market value of this was more than $ 10,000 but, after some discussion, resisted the temptation to cash in and set aside half of it to be used later. The other half was to be used to prepare the pure trans acid. Now Fitz explained that in the industry, it was customary to convert the cis to the trans by heating the oleic acid with a lot of elemental selenium, and this treatment would convert the cis oil to an equilibrium mixture rich in the solid trans acid. Well, he did this and then spent several weeks earefullly purifying the trans acid. Finally he showed me, with considerable pride, his bottle of beautiful white crystals. I said. “Fitz, my old mentor at OSU always liked to give a final purification of a compound by distilling it.“ Fitz objected to submitting this apparently pure material to distillation but I finaily said, “Just do me a favor and do it.“ I watched while he rigged up the apparatus to do this, which in this case consisted of a molecular still because of the high boiling point.

When finally he got the equipment to work, the distilled material started to come over through a cold condenser. Well, we both expected the material to solidify on cooling but instead it came over as a liquid! The meaning of this was devastatingly clear. After all the work to prepare the high melting trans acid, it was being converted on distillation back into the liquid cis acid!

Fitz turned to me in a rage but I was more excited than he. “Fitz,“ I said, “you have just discovered a major fact about selenium treatment that no one in this fatty acid industry knows about, even though they have been doing this selenium treatment for years! What you must have, hidden in these beautiful crystals, is a little bit of undetected selenium, and on heating it is acting as a soluble homogenous catalyst.

The art of using insoluble selenium in the solid form is an illusion. An eensey bit of the massive amount of selenium that is usually used, goes into solution, and it is this smidgin of soluble selenium that is a catalyst for the isomerization.“ Sure enough, we learned that only a very small quantity of selenium was required, and its action depended on its going into solution. But there were still complications to come. We next considered the possibility that maybe there was a very small quantity of some unknown impurity in the selenium which was the true catalyst. So we contacted the manufacturers of selenium, who were preparing it to be used in industry as rectifiers, and got them to send us the purest form of selenium they had.

And behold! when Fitz used this selenium it was dead, absolutely inert! It lay as a ball in the bottom of the flask and nothing happened! We were both pretty depressed. Although this sent Fitz nuts, it also sent him to the library. Well it turned out that this superpure selenium was a gray, crystalline form [Editor‘s Note: gray selenium consists of infinite chains of Se atoms] and we bad been using a gray amorphous form whose structure consisted of selenium bonded in rings of six atoms. Fitz learned how to convert the crystalline form to the amorphous form, and the puzzle was solved (article #4). lt was this amorphous form that was active and it dissociated in solution to give Se radicals, the catalytic isomerization turned out to be a radical chain reaction. We forgot about the oxygen stuff and turned to the catalyst stuff. We published this chemistry in Journal of the American Chemical Society (article #l). The discoveries that Fitz worked on in the fatty acid work were applied to other systems and we published a series of articles dealing with selenium chemistry.

In order to show that a hydrogen adjacent to the double bond was not essential, Fitz found that Se radicals catalyzed the isomerization of cis to trans stilbene, molecules that do not possess a hydrogen atom on a carbon adjacent to the double bond (article #3).

1. The Selenium-Catalyzed Cis-Trans Isomerization of 9-Octadecenoic (Oleic-Elaidic) Acids, Journal of the American Chemical Society, 79, 4765-71 (1957). J. D. Fitzpatrick and Milton Orchin.

2. Quantitative Analysis by Ultraviolet Spectrophotometry, Journal of Chemical Education, 34, 496-99 (1957). M. Ish-Shalom, J. D. Fitzpatrick and Milton Orchin.

3. Selenium-Catalyzed Isomerization of Cis-Stilbene, Journal of Organic Chemistry, 22, 1177-79 (1957). J. D. Fitzpatrick and Milton Orchin.

4. Fate of the Selenium in the Isomerization of Oleic Acid, Journal of Organic Chemistry, 23, 918-19 (1958). J. D. Fitzpatrick and Milton Orchin. 5. A Study ofthe Selenium Dehydrogenation ofGuaiol and Related Compounds. Selenium as a Hydrogen Transfer Agent, Journal American Chemical Society. 82,
639 (1960) William T. House and Milton Orchin.

6. Aromatization Reactions with Selenium and Aryl Diselenides. Journal of Organic Chemistry,27, 3401 (1962) Hartley A. Silverhood and Milton Orchin

7. Photocyclization-Aromatization of Stilbenes Using Selenium Radicals. A Synthesis of 2,4,5,7-Tetramethylphenanthrene, Journal of Organic Chemistry, 31,
4302 (1966) Elliott J. Levi and Milton Orchin.

In almost all reactions one has to have an analytical method for following the progress of the reaction. In the case of the stilbene system, we used ultraviolet spectroscopy and in the process worked out a general method of analysis using this tool and published it in Journal of Chemical Education (article #2). Selenium had been used historically to convert partially aromatic systems to fully aromatic systems but nobody had ever bothered to find out how the Se worked.

It was clear to us that the reaction probably involved Se radicals (article #4 and #6). With our background knowledge, we then showed that Se can function as a hydrogen transfer catalyst; e.g., starting with a natural sesquiterpene (guaiol) we showed that two products resulted: a compound more saturated than the original and one less saturated (article #5). This is a beautiful reaction to run because the unsaturated compound formed is an azulene, and, as the name implies, azulene is a beautiful blue hydrocarbon because of its unusual structure. Although it is by definition an aromatic compound it behaves more like a cyclic conjugated polyene. Finally we used our knowledge of selenium catalysis to prepare a derivative of 4,5-dimethylphenanthrene (article #7). In some classic work Mel Newman had shown that this hydrocarbon was the flrst example of a group of compounds that he called overcrowded molecules. The overcrowding prevents the molecule from being planar. Newman showed that such molecules occur in two forms that are non-superimposable mirror images of each other and are therefore optically active. But Newman had to resort to tricky synthetic schemes to obtain his compounds, while we found we could produce it readily in a one-step reaction.

I have chosen this example with selenium for several reasons. It shows something that frequently happens in academic research when a chance observation can be pursued without the necessity of justifying it to some bottom-line, cost-conscious administrator. What started out with one goal in mind was completely transformed into another area of research. In choosing what kind of research to do at a University, I use two simple criteria :

Is what you want to do both original and significant?
Is it doable?

If the research meets these two criteria and is successful, then it is likely to warrant publication. It seems to me that publication of research is a necessity, especially if done in a public University; otherwise it is only meaningful to the person who has done it, remains forever in a notebook, unavailable to the public who paid for it. It is important, even imperative, that University research results be made available. One never knows how the new knowledge may be applied.

I don‘t know of any particular commercial use that has been made of our research on selenium, but it has added to our understanding of a lot of chemistry. At the time we were doing this work, selenium was regarded as a very toxic material to be avoided at all costs. But today selenium pills are taken as a dietary supplement. It is in the same family as oxygen and sulfur. Its exact function is not understood and, although nobody has suggested that its biological activity may result from its radical chemistry, such a possibility exists.

         
   Editor‘s Note: The biochemistry of selenium is a very active field of
   current research. Selenium apparently has several functions. The amino acid
   selenocysteine can be incorporated into proteins and occurs in the antioxidant
   enzyme glutathione peroxidase. which controls H-,O, activity in aerobic cells
   [Wolinsky & Driskell. ed. Sports Nutrition. CRC Press, 1997, pp 195-204].
   Selenium and Vitamin E serve as synergistic antioxidants.
   The ability of selenium to undergo electron transfer may be a crucial
   part of its biological function.

After this long exegesis on how student research work can result in new chemistry, I want to discuss the second example dealing with how classroom teaching helped me learn so much from my students and peers. It came about as a result of teaching a particular course. To put this into perspective I must tell you how it was that I was teaching this particular course. When I came to the University of Cincinnati I had a special interest in ultraviolet spectroscopy {set in bold font by this website}.

I had already co-authored a book on the subject but I realized I didn‘t understand a lot of the theory. It was my good fortune that there was a recent addition to the chemistry faculty who did understand the theory, Hans Jaffé {set in bold font by this website}. Under my persistent questioning it occurred to both of us that we should undertake a book on the subject. Thus began the most stimulating and productive part of my career in teaching. First Hans taught me about symmetry. Selection rules, which govern how intense an absorption will be, are based on symmetry. Gradually I began to appreciate how important the concepts of symmetry are, how pervasive symmetry is in nature as well as science, and how an understanding of symmetry can enhance one‘s appreciation of music, art, arcbitecture, biology, physics, mathematics, especially group theory, and (of course!) chemistry.

Then Hans taught me about molecular orbital theory, because ultraviolet absorption spectroscopy is about electrons in orbitals and where these electrons go when they take up energy supplied by ultraviolet light. In the course of writing the book we would argue incessantly with a lot of shouting, sometimes about each other‘s deficiencies, in rather impolite language. We did a lot of writing while sitting together in my office in the basement of the old Chemistry Building. The chair Hans occupied had a tendency to be unstable when pushed too far back; frequently Hans took it past its equilibrium position, and he and the chair crashed to the floor. When this happened, his reaction was such that occupants of the other floors thought an unlikely earthquake had struck the building.

After three years of hard work we finally got the book out (without replacing the chair); I must say it was a huge success and became known as the Old Testament of Ultraviolet Spectroscopy. We followed that with four other books, the last of which was called Symmetry, Orbital and Spectra or SOS. This was designed as a textbook and I started to teach a graduate course called SOS. The fact that I was Head of the Department at the time made it somewhat easier to make the course a requirement in the first quarter of graduate study in chemistry. I had a lot of fun teaching that course, and I was lucky to have some very talented students take it seriously and, in the process, point out to me improvements in my presentation and understanding sufficiently fundamental to warrant publication.

Two graduate students in particular were prominent in this regard. Nelson Phelan and Chao-Yang Hsu. I think I taught the course for about 5 years, and each year it seemed that something not completely clear would come up in the teaching. Nelson Phelan, who was my assistant in the course, pointed out better ways to present certain ideas, and, in addressing his insights we published a series of tbree articles in Journal of Chemical Education :

1. Symmetry Simplifications in Calculations of HMO Wave Functions, Journal of Chemical Education, 43, 57 1-75 (1966). N.F. Phelan and M. Orchin.

2. A Molecular Orbital Description ofthe Non-Classical Ion in 1,2-Rearrangements, Journal of Chemical Education, 44, 626-35 (1967). N.F. Phelan, H.H. Jaff~, and M. Orchin.

3. Cross Conjugation, Journal of Chemical Education, 45, 633-37 (1968). N.F. Phelan and M. Orchin.

4. A Simple Method for Generating Sets of Orthonormal Hybrid Atomic Orbitals, Journal of Chemical Education, 50, 114-118 (1973). C.-Y. Hsu and M. Orchin.

The article on the molecular orbital treatment of the non-classical ion seemed to reconcile the parties in the classical-nonclassical disputations, which were very prominent in the sixties. In any case the three articles, stimulated by Nelson, represent extensions of the course work that were quite useful.

It is just the kind of development that professors hope occurs; some bright student in the class will see something, question something or see some new way of presentation that the professor had not thought of. It exactly proves my frequently made contention that students can be great teachers. A fourth article that arose out of the teaching of SOS was one that Dr. Hsu was instrumental in getting together; it turned out to be spectacularly popular, judging by the many, many requests for reprints from people all over the world and from institutions previously unknown to me. And, I might add, they all spelled “Cincinnati“ correctly!

I have had time to give you only two examples of how much I have learned from teaching here at the University of Cincinnati. I think being a Professor is indeed a special privilege with serious responsibilities. A University is a unique institution, and I can‘t imagine a more rewarding experience than having spent my entire academic career as a professor in the Department of Chemistry at the University of Cincinnati. lt has had its off-campus rewards as well. With the opportunity to publish the research work of my students, our work has become known to many chemical corporations and I have been a consultant to many of them. These contacts have added another dimension to my understanding of the importance of chemistry to the national well-being.

In addition, it has allowed me to be a first hand witness to the way research is carried out in many corporations. It has also permitted me to make friends with many research directors and to learn the importance of factors that make for success in an industrial environment. I was struck with how frequently these directors of research had a very broad view of education and a willingness to support people and projects for the greater good of the nation. One of the most thoughtful of such people has been Emory Ford, with whom I have worked for many years and who was instrumental in promoting the publication of the booklet you have on your table. The editorial work, historical research, writing and getting out the booklet What a Privilege! as you see it, is the work of Bill Jensen of our department, who has done a remarkable job of making the University of Cincinnati known throughout the world as a center of the history of chemistry.

Finally, as all of you appreciate, affairs such as this just don‘t happen; organization and people make it happen. So I want to thank my colleagues Al Pinhas and Marshall Wilson, and that indispensable secretary and arranger of chemistry department affairs, Kim Carey. I would like to close with a quote from a book I have on my bookshelf at home, entitled. “The Wit and Wisdom of the Talmud“. The Talmud is the book of Jewish law and commentary. The commentary frequently consists of asking a question solely for the purpose of answering it. One of the questions, in Hebrew, is “aza chochom“, (who is a wise person)? A wise person, the Talmud instructs, is a person who learns from everyone.

Wisdom can‘t be taught, but it can be acquired. Teaching has provided me with a lifetime of learning. And so I thank so many students, colleagues, and friends. I have learned so much from so many of you in the pursuit of wisdom. My sincere thanks to every one of you for coming and being with me to share in this touching and meaningful occasion.

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