Geuther, Anton

(b. Neustadt near Coburg, Germany, 23 April 1833; d. Jena, Germany, 23 August 1889)

chemistry

Geuther was the son of Christian Friedrich Geuther, a master weaver, brewer, and farmer who was also municipal treasurer of his native city. His mother was Anna Cordula Eichhorn. In accordance with his father’s wishes, Geuther learned the weaver’s trade and after his apprenticeship attended the Realschule in Coburg and, later, the one in Saalfeld. At Saalfeld he was more attracted by the scientific than by the commercial and technical subjects and thus, following the certificate examination, decided to study science. He entered the University of Jena, where among his teachers were H. W. F. Wackenroder (chemistry) and Matthias Schleiden (botany). He went to Göttingen in 1853 where, except for a semester in Berlin (the winter of 1853–1854), he remained for ten years. He attended lectures on mineralogy, physics, organic chemistry, and philosophy but, most important, he was for years an assistant to Friedrich wöhler. He received his doctorate in 1855 and then advanced through various posts in Wöhler’s institute, becoming successively lecture assistant, private assistant, head assistant, Privatdozent (1857) and associate professor (1862).

In 1863 Geuther went to the University of Jena as a full professor. In the same year he married Amalie Agnes Sindram, the daughter of Wilhelm Sindram, director of a hospital at Göttingen. They had one son and one daughter. Geuther remained in Jena for the rest of his life, achieving success both as a researcher and as a teacher. Great demands were made on Geuther’s idealism, for although his summerhouse had been equipped for chemical research through the patronage of Grand Duchess Sophie, of Saxe-Weimar, it was never adequate to his needs. A new structure had already been agreed to when, in 1889, he contracted typhus—and he did not live to see it built.

Under wöhler’s influence Geuther’s years at Göttingen were devoted primarily to inorganic chemistry. Geuther was a strict adherent of J. J. Berzelius’ dualistic, electrochemical conception; the substitution theory, which was rapidly gaining prominence, appeared to him insufficient “if it is a question of real insight and reduction to general principles.” Geuther interpreted his extensive investigations of double compounds in the light of the dualistic theory and discussed the constitution of these compounds in a manner that suggests Alfred Werner’s interpretation of complex compounds.

In Jena, where organic chemistry took precedence in his work, Geuther made his most important discovery, the synthesis of acetoacetic ester. The starting point for this achievement was his investigation of the constitution of alkyl compounds; among them was acetic acid, which, as the result of a then-common but false assumption concerning the atomic weights of carbon and oxygen, Geuther thought to be dibasic. Through the reaction of metallic sodium and acetic ester, he hoped to obtain the dibasic sodium salt of acetic acid; instead the result was acetoacetic ester. Geuther determined the composition of this previously unknown substance ánd ascertained its great reactivity. Moreover, from the color reaction with ferric chloride characteristic of phenoloid compounds and from the green color of the copper salts, he inferred the presence of an acidifying hydroxyl group in the molecule. A long controversy with Edward Frankland and Baldwin Duppa, who suspected that a ketonic form was involved, was not settled until 1911, when Geuther’s successor Ludwig Knorr demonstrated that demonstrated that under normal conditions both substances exist in the compound. As the first example of a keto-enol tautomerism, acetoacetic ester was of great significance in the development of theoretical organic chemistry.

BIBLIOGRAPHY

I. Original Works. Lists of Geuther’s publications may be found in Poggendroff, vols. III, IV, and VI. The most important are Lehrbruch der chemie (Jena, l869); “Untersuchungen über die einbassichen Säuren,” in Nachrichten von der Gesellschaft der Wissenschaften zu Göttingen (1863), p. 281; “Untersuchungen über einbasische kohlenstoffsäuren, ü die Essigsäure,” in Jenaische zeitschrift für Medizin und Naturwissenschaft, 2 (1866), 388; and “Uber die Constitution des Acetessigesters (Aethyldiacetsaäre) und über die jenige des Benzols,” in Justus Liebigs Annalen der Chemie, 219 (1883), 119–128.

II. Secondary Literature. Works by his pupils that show Geuther’s immediate influence includes C. Duisberg, “Beirtäge zur Kenntniss des Acetessigesters,” in Justus Liebigs Annalen der Chemie, 213 (1882), 133–181; and Wilhwlm wedel, “Über einige Abkömmlinge des Acetessigesters,” ibid., 219 (1883), 1–119.

On Geuther and his work see C. Duisberg and K. Hess, in Berichte der Deutschen chemischen Geselschaft, 63A (1930), 145–157, with portrait; C. Liebermann, ibid., 22 (1889), 2388; and Neue deutsche Biographie, vol. VI.

Grete Ronge