Nave, John

Young years

John Ulrich Nef was born on June 14, 1862 in the city of Heriso in Switzerland . In 1866, he, along with his family, moved to Hausotonic, Massachusetts . Initially, John attended a school in Hausotonic, but a year later his father transferred him to Great Barrington School so that his son received a good education. John studied there for eight years, from 1869 to 1877.

When John Ulrich was sixteen years old, it was decided that he should go to college, preferably to Harvard . Therefore, he spent two years at a preparatory school at New York College. In 1880, Nave entered Harvard University . Initially, he planned to become a doctor, but became interested in chemistry. In his first year, he was elected to the Phi Beta Kappa student order. In high school, he was awarded a Kirkland scholarship, which allowed him to study in Europe from 1884 to 1887.

In 1886, in Munich, the Nave received an honors degree. He performed research for the diploma under the guidance of Bayer and wrote the work “On Benzoquinone Carboxylic Acids”. Subsequently, John Ulrich became interested in the problems of tautomerism, a phenomenon that Bayer first discovered, and remained in the laboratory in Munich for another year.

Further career

In 1887, Nave accepted an assignment at Purdue University, Lafayette, Indiana . He plunged into a period of intense research and development, as a result of which he published three articles in the American Chemical Journal, one of which was reprinted in German at Liebigs Annalen. In 1889, Nefu signed a three-year contract as an assistant professor of chemistry at Clark University, Worcester, Massachusetts. After the resignation of Professor Arthur Michael in April 1892, Nef was appointed head of the chemical laboratory. In 1891, funding difficulties arose at the university, and a year later eight leading teachers resigned. Among them were J.W. Nef, associate professor of chemistry. In the same year, Nave was invited to the new University of Chicago, sponsored by John D. Rockefeller. From October 1, 1892, John Ulrich was appointed professor of chemistry, which he held throughout his life.

Scientific organizations of which John Ulrich Nef was a member:

* American Chemical Society (1885)

* German Chemical Society (1885)

* American Association for the Advancement of Science (Secretary, Section C, 1893)

* Chicago Academy of Sciences (1893)

* National Institute of Social Sciences, New York (1914)

* American Academy of Arts and Sciences (1891)

* Royal Scientific Society in Uppsala (1903)

* National Academy of Sciences (1904)

Teaching activities

Nave instilled in his students a love of research and hard work, accuracy and methodology in conducting experiments. J.W. Nef contributed to the creation of an assistant professor of chemistry at American universities for employees who defended their doctoral dissertation. For the first time, Dr. W. Papke, a student of Victor Mayer (Clark University), was appointed assistant professor. During his teaching career, Nef prepared 25 candidates of science.

First works

The research activity of John Ulrich Nef began with the thesis “On Benzoquinone Carboxylic Acids” ^[1] , carried out under the supervision of Adolf von Bayer and published in 1886. Since 1887, Nef continued his studies at Purdue University, Lafayette, Indiana. The first independent work of Nef was associated with derivatives of β-benzoquinone and criticized the work of A. Hange ^[2] . As a result of these studies, Nef accurately and thoroughly described a large number of compounds. On this subject, he published three articles in the American Chemical Journal, one of which was republished in German at Liebigs Annalen.

Prerequisites for Modern Radical Theory and Transitional Theory

J.W. Nef and his school dealt with the chemical reactivity of carbon compounds. Their work was preceded by modern radical theory and the modern theory of the transition state. Since the electronic nature of the covalent bond was not known at that time, Nef emphasized the numerical value of valency and the initiation of bond dissociation in the reaction. He began by criticizing the Kekule concept that carbon valency is always four and studied compounds such as carbon monoxide, isocyanides and fulminates ^[3] , in which carbon has a lower valency. Nef found that in these substances the valency of carbon varies from 2 to 4 with the addition of one unsubstituted carbon atom. He believed that carbon compounds such as alkyl halides first dissociate into a reactive divalent carbon radical, which can then be reacted in several ways. In studying the Würz reaction, he determined the yield of products.

This theory of dissociation was really relevant for its time ^[4] . Our modern theory of the transition state is foreshadowed by the words of Nef: “In addition to the ionic reactions, the rest of the reactions between two substances always occur due to their combination with the formation of an addition product. One unsaturated molecule, while partially in the active molecular state, absorbs the second molecule. As a result, the attachment product often spontaneously breaks down to form two molecules. ” It is now known that the main step in the formation of free radicals is the homolytic breaking of the covalent bond to produce free radicals, which can be recombined in several ways.

These radicals are not predominantly divalent, although in the case of diazomethane dissociation, modern chemists have found evidence of the existence of a transition methylene radical (“carbene”).

Modern tools of electron magnetic resonance show that free radicals can exist indefinitely when they fall into the defects of the crystal lattice. At present, Nef’s explanations regarding the reaction of obtaining Gauthier carbylamine (1869) involving dichloromethylene intermediate radicals ^{[5] are} valid.

Unsaturated Carbon Compounds

When Nef began his first work on the creation of tetrahalo derivatives of p-benzoquinone, three formulas of p-benzoquinone were used ^[6] . Of the three, one has now been adopted, established on the basis of the strong experimental base of Nef. Then he turned his attention to the sodium salts of ß-keto esters, in the formula of which, as he believed, the metal should be attached to oxygen, and not to carbon. After the sodium salts of ß-keto esters, Nef began to study the sodium salts of primary and secondary nitroalkanes. He insisted on the enol structure for salt and showed that the acid is not reduced from nitroalkane, but the formation of a carbonyl compound occurs ^[7] . A method of synthesizing a carbonyl compound from a nitroalkane salt is known as one of the Nef reactions ^[8] . Nave established the true formula of the fulminates, which Liebig and Gay-Lussac had previously described as salts of dibasic acids. He recognized that the carbon atom in fulminic acid is most likely divalent ^[9] . As a convincing evidence of this fact, he identified fulminic acid hydrohalide.

Nave also studied hydrocyanic acid, its salts and alkyl isocyanides. He became interested in the specific compound 2 (RNC) · 3HCl and substances obtained by the action of alkyl hypochlorites on metal cyanides. He preferred the structural formula H-N = C for hydrocyanic acid and, like many organic chemists of his time, he did not like tautomerism or the movement of structures, stating that "to explain the behavior of an organic compound, one formula is enough." He conducted research on truly divalent carbon compounds, which he began with assumptions about the role of divalent carbon in all other organic reactions ^[10] . These assumptions, supported by a large number of experimental data, were published in four long articles in Liebigs Annalen.

Nef has studied a large number of unsaturated carbon compounds, including acetylene. He obtained and studied mono- and di-halogen-substituted alkynes, which were poisonous and spontaneously combustible compounds. In the course of his research on the chemistry of acetylene, Nef set the acylation of ketones, a reaction that is used today and is a key stage in the commercial synthesis of Vitamin A ^[11] .

Sugar Dissociation

In the last period of his life (1904-1915), Nef studied the dissociation of sugars in the presence of alkalis of different strengths and various oxidizing agents in neutral, acidic and alkaline environments. The results of these studies were presented in three long articles at Annalen, appearing at three-year intervals under the name “Dissociations in the Sugar Group”. The experiments were carried out in the hope that they would shed light on the process of fermentation of sugars.

Nave isolated saccharin acids (alkaline products of the restructuring of reduced sugar) and established their structure. Together with Oscar Hedenburg, he discovered a second crystalline form of the glucono- (and mannono-) lactone, now known as the unstable 1,5-lactone. From aldonolactones, he synthesized their acyclic esters. Nave showed that the oxidation of an alkaline solution of aldonic acid by air flow led to a decrease in the concentration of aldose. Dr. Ulrich used the concept of the formation of endiol in explaining the complex changes caused by the action of alkali on sugar ^{[12] [13] [14]} .

John Ulrich was the eldest of the two sons of Johan Ulrich and Anna Katerina Mok-Nef. His father worked in a textile factory and in 1864 immigrated to America, becoming interested in the possibilities of the textile industry in this country. In 1866, he brought his family to the United States and built them a small house four miles from Hausotonik. His son was then four years old and he lived there until he was sixteen. Father instilled in young Nefu a love of books, music, sports and work.

In the summer of 1884, Nef went to study in Europe, accompanied by his father, who contracted tuberculosis. They spent the summer together in the vicinity of Fiervaldschtatter, and then his father returned to the United States, where he died a few months later at the age of fifty. This entrusted the responsibility of John Ulrich to care for the mother, who had health problems and died in 1910 in Heriso, where her son brought.

Although John Ulrich stated that "a scientist must be married to his science," he married May 17, 1898 in Rochester, New York, to Louise Bates Comstock, one of his students. Louise Nef was a very educated young woman who spent five or six years in Europe traveling and getting an education. She played the piano well and, having a diploma in chemistry, understood the profession of her husband. The young couple spent the summer of 1898 traveling in Europe. Their marriage was happy, but it did not last long. Ms. Nef died of pneumonia on March 20, 1909. The loss of his wife became a great grief for Professor Nef, he never married again. The only son, John Ulrich Nef Jr., was born on July 13, 1899.

One of Nef’s students, subsequently Professor William Lloyd Evans, described Nef as follows: “The nave was rather short in stature with a massive forehead and bright, penetrating eyes. He had an all-consuming and contagious love for his science. Everyone was fascinated by the speed of his thought, which was so ahead of the speed of his words that students could only make fragmentary notes. His restless pursuits of enthusiasm

about the tasks with which he was absorbed, he developed in him the appearance of sharpness, which reached almost impatience when the research did not go so smoothly. Despite these intellectual zeal, he possessed, however, virtuous human qualities. He was impulsive and spent his free time on long walks at a sporting pace. He loved music and every season he came to listen to the Chicago Symphony Orchestra every week ” ^[15] .

Personal qualities

John Ulrich Nef was a comprehensively developed person. From his youth, he became addicted to swimming and playing tennis. Nave appreciated music and art, regularly attended various concerts, having a particular passion for the work of Beethoven and Wagner. In 1889, during the summer holidays in Switzerland, the Nave became interested in mountaineering. Every summer, from 1891 to 1897, he spent in the Alps, making numerous difficult climbs. In 1908, the Nave made a difficult climb to Estes Park, Colorado, from Elkhorn Lodge to the top of Long Peak and back in one day. The summer of 1915, Nave and her sixteen-year-old son spent in the Canadian Rockies. However, he soon felt ill, and at the end of July he arrived in San Francisco. A medical examination showed that he was suffering from acute dilatation of the heart. He died on August 13, 1915.

In his youth, while diving, Nave damaged the eardrum and was practically deaf in his right ear. Although Nef was fluent in German, he used to send manuscripts to his friend Johannes Thiele for translation. Nave always kept a close eye on the order in the laboratory. There are stories about the anger that fell on the head of an unfortunate graduate student when Dr. Nef entered the laboratory and found a burned match on the floor, Nef was temperamental and impulsive, and in 1894 Rector Harper was forced to write him the following: “Your letter of April 6 was received . “I do not want you to implement the plan indicated in it and I hope that you will not commit rash acts.” One of Nef’s students, subsequently Professor William Lloyd Evans, described Nef as follows: “The nave was rather short in stature with a massive forehead and bright, penetrating eyes. He had an all-consuming and contagious love for his science. Everyone was fascinated by the speed of his thought, which was so ahead of the speed of his words that students could only make fragmentary notes. His restless pursuit of enthusiasm for the tasks with which he was absorbed, developed in him the appearance of harshness, which reached almost impatience when the research did not go so smoothly. Despite these intellectual zeal, he possessed, however, virtuous human qualities. He was impulsive and spent his free time on long walks at a sporting pace. He loved music and every season he came to listen to the Chicago Symphony Orchestra every week. ”

• Encyclopedic Dictionary . 2000.

• John Nef With Leonard P. Kinnicutt. The Volumetric Determination of Combined Nitrous Acid
• John Nef Ueber die Alkylirung der Ketone
• On the Fundamental Conceptions Underlying the Chemistry of the Element Carbon
• On the Non-equivalence of the Four Valences of the Carbon Atom .
• Photo by John Nef . chemistry.msu.edu.