20th-century French chemists

Paul Marie Alfred Lebeau (19 December 1868 – 18 November 1959) was a French chemist. He studied at the elite École supérieure de physique et de chimie industrielles de la ville de Paris (ESPCI). Together with his doctoral advisor Henri Moissan he was working on fluorine chemistry discovering several new compounds, like bromine trifluoride, oxygen difluoride, selenium tetrafluoride and sulfur hexafluoride.
In 1899 he was able to obtain pure beryllium by electrolysis sodium fluoroberyllate (Na2[BeF2]).
In World War I he improved the gas mask design used by the French army.

Prof Emil Clement Jungfleisch FRSE MIF (1839-1916) was a French biochemist and pharmacist. He studied molecular dissymmetry.

Charles Dufraisse (20 August 1885, in Excideuil – 5 August 1969, in Excideuil) was a French chemist. With Charles Moureu, he conducted pioneer research of autoxidation and antioxidants.
In 1921 he received his doctorate at Paris with the thesis Contribution à l'étude de la stéréoisomérie éthylénique, and served as an associate director in the laboratory of organic chemistry at the Collège de France. In 1927 he was named a professor at the École supérieure de physique et de chimie industrielles de la Ville de Paris, and in 1942 became a professor at the Collège de France. He was cofounder of the Institut français du caoutchouc (French Institute of Rubber).

Stéphane Marcel Delépine (19 September 1871, in Saint-Martin-le-Gaillard – 21 September 1965) was a French pharmacist and chemist, whose name is associated with the Delépine reaction for the preparation of primary amines.
He studied at the Sorbonne and at the École Supérieure de Pharmacie in Paris, receiving his doctorate in 1898 with the thesis Amines et amides dérivés des aldéhydes ("The amines and amide derivatives of aldehydes"). From 1895 to 1902 he served as préparateur at the Collège de France, where he worked in the laboratory of Marcellin Berthelot. In 1902 he was named chief pharmacist to the hospitals of Paris, a position he maintained up until 1927.From 1904 he was an agrégé at the École Supérieure de Pharmacie, attaining the chair of hydrology and hygiene in 1913. In 1930 he was appointed a professor of organic chemistry at the Collège de France.In 1927 he became a scientific advisor for Etablissements Poulenc, and subsequently was named director of pharmaceutical research for Rhône-Poulenc. In 1930 he became a member of the Académie des sciences.His work involved research in the fields of organic, inorganic and general chemistry. He made contributions in his investigations of terpenes, platinum group metals (iridium, rhodium), sulfur compounds, et al. In 1935 he described a general method for catalytic hydrogenation with Raney nickel. Also, when experimenting with thiocarbonic esters and related bodies, he discovered the phenomena of "oxyluminescence". In addition, he is credited for introducing a new process for preparation of pure tungsten.

Émile Bourquelot (21 June 1851 – 26 January 1921) was a French chemist, and professor of pharmacy at the University of Paris. He was born in Jandun (Ardennes, France), to a farmer, and was the eldest of three sons. Bourquelot became the Chief Pharmacist at the Laënnec Hospital in 1887, where he established a laboratory to conduct his research into carbohydrate chemistry. Bourquelot and other French pharmacists pioneered the study of plant glycosides, molecules in which a sugar is bound to a non-carbohydrate part. They developed methods to stabilize these compounds in solution, and detect them enzymatically. He died at the age of 70 on 26 January 1921 of pneumonia.
The French Academy of Sciences awarded him the Prix Montagne for 1897.

Philippe Antoine Francoise Barbier (2 March 1848 – 18 September 1922) was a French organic chemist. He is best known for his two named reactions in organic synthesis, the Barbier reaction and the Barbier-Wieland degradation, as well as for his role in the creation of organomagnesium reagents with his student, Victor Grignard.
Although Grignard was awarded the Nobel prize in 1912 (along with Sabatier) for his discovery, Barbier and Sabatier’s collaborator, Senderens, were snubbed. Grignard himself decried this as an injustice, writing to a friend just days after returning from his Nobel acceptance: “…to tell the truth, and between us, I would even have preferred to wait a little longer, to see the prize shared between Sabatier and Senderens, and then share it myself with Barbier at a later time”. Nevertheless, Barbier’s contributions to the scientific community were plentiful and varied, including work in mineralogy, natural products isolation, and polycyclic aromatic hydrocarbons.

Georges Claude (24 September 1870 – 23 May 1960) was a French engineer and inventor. He is noted for his early work on the industrial liquefaction of air, for the invention and commercialization of neon lighting, and for a large experiment on generating energy by pumping cold seawater up from the depths. He has been considered by some to be "the Edison of France". Claude was an active collaborator with the German occupiers of France during the Second World War, for which he was imprisoned in 1945 and stripped of his honors.

Pierre Potier (22 August 1934 – 3 February 2006) was a French pharmacist as well as a chemist. He held the position of Director of the Institut de Chimie des Substances Naturelles (1974 to 2000), as well as a teaching position at the Muséum national d'histoire naturelle. He was a member of the Académie nationale de pharmacie, the Académie des sciences, the Académie des technologies and the Academia Europaea.

Guy Henry Ourisson (March 26, 1926 – November 4, 2006) was a French chemist. He was a member of the Academy of Sciences where he was vice president and then became the president. Awarded the Ernest Guenther Award in 1972 and the Heinrich Wieland Prize in 1985.

Raymond Daudel (2 February 1920 – 20 June 2006) was a French theoretical and quantum chemist.
Trained as a physicist, he was an assistant to Irène Joliot-Curie at the Radium Institute. Daudel spent almost the entirety of his career as professor at the Sorbonne and director of a laboratory of the Centre National de la Recherche Scientifique (CNRS). He is quoted as saying that the latter "was much better because the CNRS was very rich". This allowed Daudel to attract many co-workers from elsewhere in France and internationally.
Raymond Daudel was Officier de la Légion d'honneur and Officier de l'Ordre National du Mérite. He served as President of the European Academy of Arts Sciences and Humanities, in Paris, France. Daudel was a founding member and Honorary President of the International Academy of Quantum Molecular Science.An author as well as an academic, Raymond Daudel authored several books, including Quantum chemistry, originally with R. Lefebyre and C. Moser in 1959 (Interscience Publishers, Inc., New York) and later with G. Leroy, D. Peeters, and M. Sana, published by Wiley in 1983. He was responsible for the organization of the first International Congress in Quantum Chemistry, held in Menton, France in 1973.