Delépine, Stéphane-Marcel

(b. St.-Martinle- Gaillard [Seine Maritime], France, 19 September 1871; d. Paris, France, 21 October 1965)

chemistry.

With his mother’s encouragement, Delépine followed in the footsteps of his older brother by studying pharmacy. He received his professional training in Paris, where he studied pharmacy at the École Supérieure de Pharmacie and science at the Sorbonne. From 1892 to 1897 he served as intern in pharmacy and from 1902 to 1927 as pharmacist of the Hospitaux de la Ville in Paris. In 1898 Delépine became docteurés sciences physiques. From 1895 to 1902, he was preparateur to the famous chemist and statesman Marcellin Berthelot at the Collège de France, where he worked on thermochemical determinations and remained until Berthelot’s death in 1907.

In 1904 Delépine was appointed agrégé at the École de Pharmacie, where he was promoted in 1913 to the rank of professor. He remained there until 1930, when he succeeded Charles Moureu as professor at the Collége de France, thus occupying the chair once held by his mentor Berthelot. Although he inspired a number of students, including Raymond Charonnat and Alain Horeau, his successor, Delépine preferred to do most of his own laboratory work. His retirement in 1941 did not decrease his prolific scientific productivity; during his retirement he added some sixty publications to his 200 articles. He continued to work in his laboratory with the aid of an assistant until six weeks before his death at the age of ninety-four. A scientist of international reputation, Delépine was a member of many societies and was the recipient of numerous honors.

Délepine’s work encompassed almost all fields of chemistry. Like Alfred Werner, of whose work he was an ardent proponent, he began his long and fruitful career as an organic chemist. The thesis for his degree in pharmacy dealt with the separation of methylamines by formaldehyde, and his doctoral dissertation involved a primarily thermodynamic study of the amines and amides derived from aldehydes. His name is immortalized in the so-called Delépine reaction for the preparation of primary amines. He determined the structure of aldehyde ammonia and demonstrated the reversibility of the formation of acetals. Delépine’s voluminous work on organic sulfur compounds included studies of dithiourethanes, the discovery of the monomeric sulfides of ethylene (whose existence had been considered impossible), and the recommendation of dithiocarbamates as analytical reagents. He discovered that certain compounds containing doubly bound sulfur have the property of spontaneous oxidation accompanied by phosphorescence (oxyluminescence). He also made extensive studies of catalytic hydrogenation in the presence of Raney nickel. His organic work also dealt with terpenes, heterocyclic compounds, pyridine compounds, alkaloids, and aminonitriles.

In the field of inorganic chemistry, Delépine immediately adopted Werner’s then controversial views, and his numerous studies of coordination compounds, particularly those of the noble metals, confirmed their geometric and optical isomerism and verified Werner’s coordination theory. His classical work on iridium, especially the chloro salts, pyridine derivatives, and oxalates, placed the stereochemistry of this element on a firm basis, just as Werner’s work had done for the compounds of cobalt. Delépine also perfected a method for preparing pure tungsten for use in electric light filaments. He was also a master of stereochemistry and crystallography, and he devised the method of active racemates for resolution of coordination compounds and determination of their configurations. In addition, he published several articles on the history of chemistry.

BIBLIOGRAPHY

I. Original Works. The majority of Delépine’s work was published in the Bulletin de la Société chimique de France, the Annales de chimie, and Comptes rendus hebdomadaires des séances de l’Académie des sciences. His masterly summary of the chemistry of iridium is found in P. Pascal, ed., Nouveau traité de chimie minérale, xix (Paris, 1958), 465–575.

II. Secondary Literature. R. Oesper, in Journal of Chemical Education, 27 (1950), 567–568 gives a very brief description of Delépine’s work. A 38-page booklet, Hommage rendu au Professeur Marcel Delépine par ses am is, ses collègues, ses élèves à l’occasion de sa promotion au grade de Commandeur de la Légion d’Honneur, 23 Novembre 1950(Paris, 1950), consists of eulogies describing his life and work. Two brief obituaries which discuss his life and work are C. Dufraisse, in Comptes rendus hebdomadaires des séances de l’Académie des sciences, 261 (1965), 4931–4935; and A. Horeau, in Annales de chimie, 1 (1966), 5–6. A detailed description, evaluation, and bibliography of Delépine’s work in the field of inorganic chemistry is found in A. Chrétien, Revue de chimie minérale, 3 (1966), 187–200.

George B. Kauffman