N. N. ZININ. an EARLY RUSSIAN CHEMIST1 HENRY M. LEICESTER College of Physicians and Surgeons, San Francisco, California
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HE founder of the modern schoolof organic chemistry in Russia was Nikolal Nikolaevich Zinin,= who not only pointed the way to modern thinking and modern experimental methods in a country which until his time had given almost no thought to the advances in chemistry which were then arousing the scientific world of western Europe, but who also trained a whole school of young chemists whose names became outstanding in the latter half of the nineteenth century. Zinin was born in Shusha, in the Caucasus mountains near the Persian border, on August 13, 1812, old style. Both his parents died within a few days of his birth, and the elder sister who took charge of him survived them by only a short time. The child was therefore sent to an uncle in the city of Saratov, and i t was there that he received his elementary education. Even in his gymnasium days he gave evidence of the powerful memory and the versatile mind which distinguished him in his later life. Whatever subject lie took up he strove to master, and he usually succeeded in doing so. He first devoted himself to Latin, in which he quickly outshone his fellow students. He then became interested in botany, and spent many days in collecting specimens, and as many nights in arranging them. His physical strength and endurance were great, but the statement of his student, Butlerov, that he could jump over hedges three arshins high is open to doubt, since an arshin is two and a third feet in length. Zinin originally planned to enterPthe Engineering School in St. Petersbnrg, but the sudden death of his uncle left him without the funds to carry out this plan, and instead he entered the University of Kazan in 1830. Although this institution had been founded only about twenty-five years earlier, it had already developed an excellent faculty. Zinin began his work in the mathematical division, where the outstanding professor was Lobachevskii, the founder of non-Euclidean geometry. During the three years of his course a t Kazan, Zinin twice won a gold medal for his unusual ability, and as soon as he obtained the Candidate degree, he was appointed assistant to the professor of physics. Six months later he was made lecturer in analytical mechan-
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Presented before the Division of the History of Chemistry ~ at the ninety-eighth meeting of the A. C.s., ~ o s t o ~~ , setts, September 12, 1939. 4 1' ' ' BORODINMD BUTLEROV,"Nikolai Nikolaevich Zinin," . , 2087 I. RUSS. phys. Cham. SOC., 12, 215-52 (1880); B ~ ~14, (1881).
ics, and after another year he was given the chair of hydrostatics and hydrodynamics. Although he seemed destined for a career in mathematics, a field in which he always retained a great interest, Zinin had for some time been developing an interest in chemistry, and a short time before he obtained his Master's degree in the physico-mathematical division
of the he~ was transferred ~ University, ~ ~ h to the ~chair of chemistry. Such sudden shifts were by no means uncommon in the loosely organized universities of the time, but probably few men who made them became as
eminent in their new posts as did Zinin. From the time of this appointment he was always first and foremost a chemist. In 1837 Zinin was awarded one of the recently established traveling fellowships which took him abroad for the first time. At this period Russian science was widely separated from the rest of Europe, and Zinin became one of the few Russian scientists who actually saw what was being done in the West. The importance of this journey, both for himself and for the future development of chemistry in Russia, cannot be overemphasized. He visited chemical laboratories in Germany, Switzerland, France, and England, and also devoted much attention to the current developments in medicine. A group of young Russians was then studying medicine
* in Berlin, and Zinin attended lectures in physiology, microscopy, and botany with them, a t the same time that he worked with Mitscherlich and Rose in chemistry. It was here that he gained the knowledge of another group of sciences to add to the wide interests which he always maintained. When he left Berlin, Zinin planned to pay a brief visit to Liebig's laboratory a t Giessen, and then go on to the south of France. He even made arrangements for a friend to meet him in France. However, as soon as he reached Giessen where Liebig was then carrying on several of his most famous researches, the young Russian realized the wonderful opportunity which lay open to him, and he canceled his southern trip. He remained a t Giessen for more than a year, and absorbed the full spirit of scientific research. The actual course of his future work was also largely determined a t this time, for he began work on benzoyl compounds, and with few exceptions, he continued to study these suhstances until his death.
He returned to Russia in 1840 and presented the results of his work a t Giessen as a thesis in the University of St. Petersburg. For this thesis, "Compounds of Benzoyl and the Discovery of New Substances Belonging to the Benzoyl Family," he was awarded the degree of Doctor of Natural Science. In the spring of 1841, Zinin returned to Kazan. During his absence, the chair of chemistry had been given to Karl Karlovich Klaus, the noted worker on platinum compounds and the discoverer of ruthenium. Therefore, Zinin was appointed Extraordinary Professor of Technology. Although he carried out the duties of this position in a striking manner, his real interest remained with organic chemistry, and he continued to work in that field. Almost a t once his studies led him to his most famous discovery. He undertook the systematic study of the action of hydrogen sulfideon various types of organic compounds. Among the first substances he used were the aromatic nitro compounds. When he treated nitronaphthalene and nitrobenzene with ammonium sulfide, he obtained two compounds which he called uaphthylidam and benzidam. He gave a careful and exact description of these substances, but he did not recognize their true nature. However, when he sent his paper describing them to the Annulen, the German chemist, Fritsche, who read the manuscript, a t once realized that Zinin had prepared aniline. When the paper was published, Fritsche added a note a t the end which pointed out this fact. Thus, Zinin had for the first time synthesized this enormously important compound and shown the way for a general method of 3ynthesis of the aromatic amines. qf this work .Hoffmann said thirty-eight years later, "If Ziuin had done nothing more than to convert nitrobenzene into aniline, even then his name should be inscribed in golden letters in the history of chemistry." Zinin continued the study, .and showed the general nature of the reaction by the pieparation of a number of other amines. He continued to use his own nomenclature in all his papers on the subject, speaking of semi-benzidam and benzaminic acid, which we now call phenylene diamine and aminobenzoin. The work was a logical and connected whole, and showed well his outstanding ability in research. The remaining years of his stay in Kazan were occupied with the extension of his studies of these compounds into the field of azoand azoxy-compounds, which he examined in great detail. He also prepared a number of derivatives of naphthalene. In his theoretical ideas, Zinin was a strong supporter of the ideas of Liehig. In this field he often ran counter to the opinions of his colleague, Klaus, who remained faithful to the dualistic doctrine of Berzelius. However, Zinin always kept abreast of the latest theoretical developments, and with his advanced outlook he was in a position to guide his students in the most fruitful way. His influence among the students grew steadily, and thoueh he did not teach chemistrv directlv. ,. he was quickly surrounded by an eager circle of chemical stu-
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dents. The most famous of these, Butlerov, gives this description of him in about 1846, "He was of medium height, broad shouldered and broad chested, with a spiritual face, a lively and penetrating glance, longish black hair combed back from his forehead in front and somewhat to the right. He usually spoke standing, and from first to last, held his hearers under the spell of his talk." His advice and council were not confined to the chemistry students. His wide interests and experience enabled him to help those who were preparing dissertations in anatomy or entomology, and they found in him both aid and inspiration. In the laboratory, Zinin encouraged his students to work individually, and he maintained a friendly attitude a t all times. Butlerov tells us, "Sometimes, when he deserved it, a student received a half-jesting scolding, accompanied by a blow. No one was offended, since he was fully entitled to answer the professor in the same way, but those attempting such an answer were few, because the attempt usually led to regret. Zinin possessed great muscular s k n g t h , and in such cases, he squeezed his opponent as if in a press. All this was accompanied with a laugh on both sides and by the bystanders." The laugh on the part of the student may sometimes have been a little forced. Combustions a t that period were events which required much labor, both in preparation and performance. Zinin usually set aside certain days for running these. In the morning the coal furnace would be prepared by the laboratory assistant, and in the afternoon, with his coat removed and his face reddened by the heat, Zinin would sit beside the furnace, carefully adding pieces of coal a t the proper points, and a t the same time discussing the latest problems with a group of students which always surrounded him a t such times. Many of his most valuable and inspiring suggestions were given under these conditions. In 1845 Zinin married an elderly,widow with a family of grown sons. Butlerov says that this was "a union of friendship and convenience; the widowfwas supported by a husband, and Zinin had a housekeeper who cared for his home and allowed him to devote himself more fully and carefully to his scientific activities." A year or two later, however, this first wife died. In 1847, Zinin was called to the chair of chemistry in the Medico-Surgical Academy of St. Petersburg. This break in his routine also caused a break in his scientific studies, and it was several years before he again began to publish a t his previous rate. Shortly after his arrival a t the capital, Zinin again married, and by this second marriage he had two daughters and two sons, one of whom later became professor of mathematics a t the University or Warsaw. It was not long after reaching St. Petersburg that Zinin again became the center of a group of enthusiastic students. His wide interests were given full play in his new surroundings, and his earlier attention to medicine enabled him to appreciate and assist in much of the work which was going on in the Medico-Surgical
Institute. In his lectures to the medical students he stressed the scientific viewpoint as the prime mover in all medical progress. He believed that all physicians should work for a time in one of the basic sciences. While "anatomy gave an understanding only of the structure of the organism, physics and chemistry gave the key to the working of all the complexes, to the infinite number of physiological and pathological changes which were carried on in it." With these ideas in mind, he gave his courses in inorganic and organic chemistry as fully as if he had been teaching in the physico-chemical division of the university. Shortly after he assumed his new duties, Zinin learned of the theories of Gerhardt and Laurent, and he quickly recognized the revolution in chemical thought which resulted from them. He became the first chemist in Russia to adopt them, and he did much to spread these important conceptions among his colleagues. In particular, he inspired Butlerov to throw aside the old ideas which Klaus had taught the brilliant young chemist, and thus to begin the career which was so important for all chemistry. During his time in St. Petersburg, Zinin was kept busy on a large number of government tasks, outside the scope of his normal duties. However, he possessed tremendous energy and vitality, and through all his other activities he pursued his studies of the benzoin compounds. The laboratory of the Academy was very primitive, and there were almost no funds for its support. Nevertheless, there was no lack of students anxious to work with the popular professor, and Zinin devoted much of his time to them. The best known of this later group was the f a m o p chemist and musician, Borodin. .. Until new laboratories were built in 1867, however, Zinin did his own work in his private laboratory a t home. This room was filled to overflowing with apparatus, books, chemicals and equipment, and no one but Zinin was allowed to touch. anything. In his personal living quarters the sam'e state prevailed. Borodin explains that when Zinin moved into his new house, he did not have time to arrange his effects, and before he could do so, he learned where eveqthmg was. After that, he considered the effort of learning new positions for his belongings to be useless, and matters were left as they had-been. His remarkable memory was guide enough. Thus, in the words of Borodin, "I once happened to see this occur. An argument came up with a physiologist. Zinin, who understood physiology well, cited by heart the support for his statement and then, recalling under which chair lay the paper he desired, he a t once went to it, without hesitation took from a dusty pile a book, opened and read i t to show he was right, and then returned the book to its former place." In his private life, Zinin was almost ascetic. He never smoked or drank, and, if possible, he avoided others who were smoking. He controlled his diet very rigidly, and often ate very little. In 1867 Zinin was made Director of the Laboratory
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at the Academy, and in 1868 he was elected president of the Russian Physico-ChemicalSociety. He held this position for the next ten years. In 1874 he retired from the Medico-Surgical Academy and devoted himself to work in the St. Petersburg Academy of Sciences, of which he was an active member. In 1860 the Customs House had seized a large quantity of bitter almond oil which had been falsely declared. This was turned over'to Zinin, and from that time on he worked largely on various benzoyl compounds. He prepared and studied a large number of such substances, thus continuing the work he had begun with Liebig. He also worked at various times on ally1 compounds, which he called propenyl derivatives, on substituted ureas, mustard oils, and the azoxy compounds previously mentioned. In aU his papers, his style was notable for its clearness and for
the logical deductions drawn from the experiments which he described. His data were remarkably exact, and he made it a point to study all reactions in as quantitative a manner as possible. Zinin continued his active chemical work until the autumn of 1878. At this time he became ill, and was forced to leave the Laboratory. For several months he continued to hope that he would be able to return to his studies, but he gradually grew worse, and on February 6, 1880, he died. Zinin may justly be credited with founding the modem science of chemistry in Russia, and showing the ability of Russian chemists to the outside world. The organic chemist owes him a particular debt for the influencewhich he had on the development of Butlerov and the latter's contributions to the theory of chemical structure.
