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lished under the title “Some Reactions of Acetylene.” This system. I know he won’t, however, for it was he who first subject has been practically the object of his study ever gave me the definition of a gentleman as a man who can play since. To me and to most of the students a t that time, who the saxophone and doesn’t. This fine appreciation of many in the College of Arts and Letters were pursuing with more things beyond his special field has made hi3 fellom7 professors or less enthusiasm the delights of classical and modern literaappreciate his delightful companionship and be glad of his ture, these “reactions” were merely words. lt was my good presence a t any and all their gatherings, He has had an ear or bad fortune, however, to witness one of hhose reactions and an eye for every occasion, and he rarely talks shop when which inspired me with a lasting respect, for this powerful outside his laboratory unless perhaps he walks with one of gas. his students or a fellow chemist. This may be a virtue of all chemists to observe the scriptural inj unction of a~otcasting Through the advice of Dr. Nieuwland there \vas installed pearls before Berkshires lest they turn and trample them. in the seminary where I lived, a system of illumination by But the chemist, Iilie murder, will out, acetylene gas. The mechanism which generated the gas was housed in a small structure back of the main building. One NE day when Dr. Nieumland’s very Democratic stomach day tlie gas flow was sluggish or jittery and tlie tinner vith a went Republican and taxed his patience and his strength, helpmate was sent down to investigate. They drained all he was sent to the local hospital, h frightened nurse came the gas out of the pipes, and then in order t o find the trouble in with a small glass of something to make rebellious s‘tomachs they lighted a match. Reactions of acetylene in the presbehave. Dr. Nieuwland took it gingerly, fanned it under his ence of the small flame of a match! T caught sight of the innose, and said, “You knov IC can’t take bromides; now, go vestigators as they were rocketed due north--and I must say back and write on your little chart ‘patient refuses to take they anticipated the auto industry by a quarter of a century medicine.’ ” What a calamity It would be if we all could even a t least, in their exhibition of floating power, knee action, and suspect what our physicians feed us. perfect stream line. If I might give a free idea to some prac1 have pictured Br. Nieuwland as going about bee-wise tical engineer, I should like to see him construct an internal one blossom to another, but through all his activity his from combustion engine for aeroplanes which would 6 ‘ c ~ m b u s t 9 ~ work in chemistry was dominant, He leaves it for a while acetylene. Then we might roll out of bed in Los Angeles, for a botanical excursion, a stay a t the beach, or a visit to old share in Chicago, and eat our wheat cakes and sirup in Kew friends-only to come back refreshed and ready for more York. labors in the laboratory where he frequently eats his meals, and not a few times catches a few hours of‘ sleep, stretched NE outstanding quality of Dr. Nieuwland and his work upon a laboratory table with an old coat or an apron for a is that it is thoroughly genuine and honest. He could pillowv. This constant, intense work has become more a joy noC fake or sham in anything, and he has no patience with than a labor and has brought the results this SOCIETY thinks or tolerance for the bluffer. This is undoubtedly the result deserving o€ special recognition, results which have made his of the scientific attitude. Men of science are usually men of own school and all its faculty decidedly proud of their own fact. I have seen him nettled by the trick photography of Br. K’ieumland. the moving pictures when the audience seemed to take as authentic what he knew to be a bit of camera deceit. I have seen that spirit of sheer honesty all through his dealings; he is frank to say “I don’t know” about many things concerning which his guess might hit closer the truth than many men’s; but he won’t guess. And if he thinks you are guessing, he is not slow to peer a t you over his half-moon spectacles and tell you the whole thing sounds &e prodigious nonsense. .And yet DP.Nieuwland is fond of fiction. One of the fine things about his life is that his rather inE. R, BRIDGWATEIP tense study of science has never cut off his interest in “cabbages and kings.” It is told in the autobiography of Darwin that he had been 80 absorbed in the study of scientific facts that he had lost all appreciation of music and poetry and the HE primary raw material. for our chemical things that appeal to the imagination and stir the feelings. industry i s f ~ n d a m e n t ascientific ~ knowlDr. Nieuwland has never lost his early interest in literaedge. Our physical raw materials-coal, ture, drama, and music. He reads voraciously and with desalt, sulfur, vegetable oils, wood pulp, etc., were available in light. I have seen him with an armful of detective thrillers almost unlimited quantity long before the birth of the chemihurrying across the campus to a quiet corner in the Science oa%industries that utilize them. We no doubt have in our Building where he could light his pipe (the most ill-smelling hands today the essential physical raw materials for new in the county) and forget for an afternoon retorts and test chemisal industries that are as yet only dimly conceived. tubes. He enjoys the movies and bobs up religiously on Their development must be preceded, as has the development Saturday night a t the university theater to laugh as heartily of every important new branch of our chemical industry, by as any freshman a t the antics of Pop-Eye the Sailor or the an advance in our fundamental scientific knowledge. growling exploits of the Big Bad Wolf. He never misses the From whence is this knowledge to come? A very small circus when it comes to South Bend. Perhaps it is his interpart of it will come no doubt from the workers in pure science est in zoology that brings him there with a couple of youngin the laboratories of the very few industrial corporations who sters tagging a t his heels; but for a scientist he seems to me support basic scientific research; but the major part of the to get a great deal of pleasure in feeding the elephants and new fundamental chemical knowledge upon which the further following the floating grace of the man on the flying trapeae. development of our chemical industry depcnds must come in. With his love of literature Dr. Nieuwland combines a fine the future, as it has in the past, from our universities, The appreciation of music. In the days that are gone he was many contributions that university research in pure science ever ready t o join with a congenial crowd and strum out has made to the development of our chemical industry are lunes on his guitar; and if he were still willing t o do it I could well known. We are particularly concerned here with the arrange for a public recital over our university broadcasting achievements of one of our outstanding chemists, Julius
rad
JULY, 1935
INDUSTRIAL AND ENGINEERING CHEMISTRY
Arthur Nieuwland, and with the contributions to our fundamental knowledge of chemistry that have resulted from his work in the laboratories of the University of Notre Dame.
D
R. NIEUWLAND’S work has had to do almost exclusively with the chemistry of acetylene. Nowhere can we find a chemist who so early in life selected for himself a small portion of the field of chemistry and cultivated that field so assiduously. Even during his undergraduate days he synthesized acetaldehyde from acetylene, using mercurous sulfate as a catalyst; that method is, in principle, identical with the present-day commercial process. While a graduate student at Catholic University he continued his work on acetylene, and we fmd in his Ph.D. thesis a statement that, while acetylene does not react with arsenic trichloride in the absence of moisture or a catalyst, it does react with arsenic trichloride in the presence of aluminum chloride. Nieuwland observed that the reaction product was extremely toxic and, presumably for that reason, did not attempt its identification. This reaction was apparently not further investigated until, during the war, W. Lee Lewis identified the toxic constituent as divinylchloroarsine and perfected the process of making it. Fortunately, however, the war was over before “Lewisite,” the name it was given, reached the front-line trenches. After his return to Notre Dame in 1904, Nieuwland’s attention was chiefly devoted to his duties as professor of botany; nevertheless he did find time to continue his work on the reactions of acetylene. I n 1906 he absorbed acetylene in a concentrated aqueous solution of sodium, potassium, and cuprous chlorides. The reaction products were not identified but he noticed a peculiar odor that seems to have made an indelible impression on his memory. When, in 1918, he was made professor of organic chemistry a t the University of Notre Dame, Nieuwland resumed his work on acetylene compounds. He studied the catalytic condensation of acetylene with aromatic hydrocarbons and with phenols, the preparation of oxalic acid from acetylene, and the reaction of acetylene and silver salts; but, most important of all, he again turned his attention to the identification of the substance having that peculiar odor which he had noticed In 1906 when he first treated acetylene with an aqueous catalyst containing cuprous chloride. He discovered that the efficiency of the catalyst could be increased by the subdtitution of ammonium chloride for sodium and potassium chlorides, and succeeded in identifying divinyl acetylene as one of the products of the reaction. Realizing that the fruits of his work would be of no benefit to mankind so long as they remained locked in his own mind, Dr. Nieuwland has generally followed the policy of promptly publishing his results, usually in the Journal of the American Chemical Society. He has also realized the immeasurable value of the personal contacts between chemists that are possible a t the meetings of the AMERICAN CHEMICAL SOCIETY. At one such meeting-the First Organic Symposium, held in Rochester in September, 1925-E. K. Bolton had the good fortune to learn from Nieuwland of his work on copper catalysts for the polymerization of acetylene. We were a t that time engaged in research looking toward the production from acetylene of a synthetic rubber that would excel natural rubber in certain respects, but our results had been most disappointing. The Organic Symposium served to bring us into closer contact with a man who has stimulated and enriched all who have had the pleasure of knowing him and who has provided for us the essential first step in the manufacture from acetylene of a polymerizable butadiene derivativenamely, a process of causing two acetylene molecules to react to form a four-carbon chain. The exact manner in which Dr. Nieuwland’s catalyst would contribute to the solution of the synthetic rubber problem
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was not immediately apparent. He had isolated and definitely identified, among the products obtained by passing acetylene through a cuprous chloride-ammonium chloride catalyst, only divinylacetylene and higher polymers, although he strongly suspected the presence of monovinylacetylene. We first attempted to produce a rubber-like polymer from divinylacetylene which normally polymerizes to resinous rather than rubber-like products. Although it was found possible to make rubber-like material from divinylacetylene, the synthetic rubbers so produced proved to have serious shortcomings that prevent their commercial use. Fortunately, however, after verifying Dr. Nieuwland’s belief that his catalyst could be made to produce monovinylacetylene, the chemists of the du Pont Company discovered the process of converting it to chloroprene (2-chloro-1,3-butadiene)by reaction with hydrogen chloride and the process of polymerizing chloroprene to make the f i s t commercially successful synthetic rubber.
THE
medalist has provided the cornerstone on which a new branch of our chemical industry is being built. But while honoring him for his outstanding contribution, let us not forget the other brilliant chemists who also contributed essential parts of the great body of scientific knowledge on which this new industry is founded. Let us remember especially Bouchardat, who may be called the father of synthetic rubber, having in 1879 polymerized isoprene to a rubber-like solid. Neither should we forget Tilden, Harries, Kondakoff, Lebedeff, Hofman, and Whitby, all of whom have made important contributions to our knowledge of the chemistry of dienes and the polymerization of butadiene and its homologs. The polymerization of chloroprene presents problems that are entirely different from those involved in the polymerization of the diene hydrocarbons, but nevertheless the background provided by these pioneer investigators was of great value in the study of chloroprene. The pioneering work of Willstiitter and Wirth, who first made monovinylacetylene and determined its physical constants, must also be mentioned. Countless other scientific men, most of them working in university laboratories, have discovered and recorded in the chemical literature facts that were brought to bear in the building of this industry. Then, too, commercial production of synthetic rubber from acetylene would be much more difficult if it were not for the corrosion-resistant alloys and other improved materials of chemical plant construction which are available today but were unknown even twenty years ago. It is so obvious as almost to escape attention that the task of the chemists and engineers who have made the commercial production of synthetic rubber a reality, would have been much more difficult, if not impossible, had they not been able to draw on the immense volume of information to be found in the chemical literature, much of it presumably quite unrelated to the subject of synthetic rubber, in addition to the work of our distinguished medalist. Likewise, the task would have been much easier if the previous knowledge of the mechanism of polymerization reactions had been less fragmentary.
W
HEN Germany, during the war, found herself in dire need of rubber and unable to obtain an adequate supply of natural rubber, she turned reluctantly to the synthetic product made by the polymerization of dimethylbutadiene. Pre-war experiments had shown it to be far inferior to natural rubber, but a modern war requires rubber in huge quantities and none other was available. Dimethylbutadiene had been made before the war from acetone, which was obtained by the fermentation of potatoes. But potatoes were required for food, and the one raw material for acetone that was available in sufficient quantities was acetylene made
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from coal through calcium carbide. It has been reported that the entire war-time German production of synthetic rubber was made from acetone derived from acetylene. Similar considerations led Dr. Bolton to the choice of acetylene as the raw material for the synthetic rubber research in which we were engaged a t the time he made the acquaintance of Br. Nieuwland, With the practically unlimited domestic reserves in this country of coal and limestone for the production of acetylene and of salt for hydrogen chloride, obviously it will be possible, if a national emergency should arise, to equip ourselves quickly to produce a sufficient quantity of chloroprene rubber to supply the nation’s needs. Moreover, acetylene can be produced from petroleum, as well as from coal, although the process is not yet fully developed on a commercial scale. Unlike the synthetic rubbers that had preceded it, chloroprene rubber has its use in times of peace as well as in war. Because of its superior resistance to oils, heat, oxidation, and ozone and sunlight deterioration, as compared with natural. rubber, and because of its low permeability to gases, there are many places in our industries and arts where it can be used to much better advantage than the natural product. These distinctive properties are making it possible to create a synthetic rubber industry in times of peace which will serve as a nucleus for expansion Ff we should be so unfortunate as to be visited by another war. If it were not for these distinctive characteristics of chloroprene rubber, its peace-time production would be possible only through the aid of a government subsidy or import restrictions, since the cost of manufacture is still far greater than the cost of growing natural rubber.
CRELY no honor has ever been more richly deserved than this award to Dr. Nieuwland, who, after devoting the major part of his academic life to the study of the reactions of acetylene, has discovered this process of acetylene polymerization which has proved to be the key to the synthetic rubber problem and the means of creating an industry that
N ORGAKIC
chemistry the branch of analysis is more difficult and varied than in the realm of inorganic chemistry; yet we may conclude that its most important use is secondary. It is absolutely necessary first of all to know not only the elements and groups, but also their relationship to one another and to the basic structure of the molecule. This knowledge is necessary in order that the synthesis of a comparatively simple substance may be effected. Analysis with proof of structure of the many thousands of compounds is absolutely a prerequisite for synthesis, since practically no progress is otherwise possible in the field of organic chemistry in modern chemical procedure. The history of synthesis of organic dyes or colors and medicinals has shown that chemists must not only have in view the preparation of nature’s products but must iinprove them, Most of these are rather transient, useless, or at least, defective. We can now make better colors and more perfect drugs than Kature. The synthetic aniline, alizarin, and indigoid dyes are more perfect than any of the colors of plants. They not only rival the rainbow in beauty but are more varied.
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is giving employment to many American chemists and workmen and will undoubtedly employ many times more in the future-an industry, moreover, that not only contributes to our peace-time civilization but adds greatly to our national security. I am sure his work will prove an inspiration to other workers in pure science, will serve to teach the deairability of concentrating one’s efforts on a small portion of the unexplored realm of chemistry, and will emphasize t o those who are in the position to lend financial support to university research the great extent to which our industrial advancement depends upon further accretions to our store of fundamental scientific data.
9 9 9 The remarks of J. M. Weiss in presenting the Nichola Medal to Dr. Nieuwland were, in substance, as follows: The William H. Nichols medal is the highest honor within the gift of the New York Section of the AMERICANCHEMICAL So-. CIETY. Since 1903 it has been presented to many famous men, When I mention Noyes, Baekeland, Langmuir, Midgley, Roger Adams, Sherman, G. N. Lewis, and Conant of Harvard as some of those so honored, it is clear that it stands for the highest type of scientific achievement. Tonight we place upon that roster one who is no less worthy. In fact, I doubt if it has ever been our privilege to recognize work in pure organic chemistry which has been of more value to our national sufficiency and self-defense. Work in Lhe chemistry of acetylene derivatives i s dangerous. We all know the extreme explosion hazards incident to many of these compounds. This field of research requires courage greater than that of the battlefield. Nevertheless, our medalist devoted himself t o t’he field which less advent,urous investigators had avoided. He persist’edand taught the world how to control these hair-trigger rea,ctions. And all t’hrough these years of work it was devotion to science without thought of materia! gain. Father Nieuwland, Soldier of Science, the New York Section of the AMERICANCHEXICAL SOCIETY is honored by your presence. It is my great privilege on their behalf, as chairman of the Jury of Award for the year 1935, t o induct you into their Legion of Honor and to bestow their Croix de Guerre-the Xichoh Medal.
Cocaine has a five-carbon ring with a toxic curare-like action Chemists have built up a molecule with the anesthetic properties of cocaine, but they have left out the poisonous part of the structure, or have replaced it with valuable, or a t least harmless, groups. Hence, we have novocaine: and other similar compounds. A. peculiar tint or shade of color or a desirable niediciiial property can now be introduced into a compound almost a t will, and its characteristics can be predicted before the preparation of the substance. Along some linea of research, however, because of slight prejudices of the investigators, lack of progress has been due to the fact that they have for decades been sat,isfied to make “something just as good” instead of starting with the ideal that the world always wants “something better.” We may cite an example in the case of the attempts to prepare a. synthetic rubber. The structure of the fundamental unit, isoprene, was sufficiently known, but chemists could not cast aside the idea that rubber is a hydrocarbon. Someone had made that definition and it would have been heresy to contradict it. Therefore, we have had numerous attempts a t imitating nature in the preparation 0% butadiene, dimethylbutadiene, and other
