Christopher Kelk Ingold
Christopher Kelk Ingold
Ingold, as photographed in Michigan State University.
28 October 1893|
London, United Kingdom
|Died||8 December 1970
|Institutions||Imperial College London
University of Leeds
University College London
|Alma mater||Imperial College London|
|Thesis||Formation and stability of carbon rings (1921)|
|Academic advisors||Jocelyn Field Thorpe|
|Notable students||Ronald Gillespie
Ronald Sydney Nyholm
|Known for||Organic reaction mechanisms
Sir Christopher Kelk Ingold FRS (28 October 1893 – 8 December 1970) was a British chemist based in Leeds and London. His groundbreaking work in the 1920s and 1930s on reaction mechanisms and the electronic structure of organic compounds was responsible for the introduction into mainstream chemistry of concepts such as nucleophile, electrophile, inductive and resonance effects, and such descriptors as SN1, SN2, E1, and E2. He also was a co-author of the Cahn–Ingold–Prelog priority rules. Ingold is regarded as one of the chief pioneers of physical organic chemistry.
Ingold began his scientific studies at Hartley University College at Southampton (now Southampton University) taking an external BSc in 1913 with the University of London. After a brief time with Imperial College, London and some war service, as a scientist, Ingold earned an MSc degree, again with the University of London. He returned to Imperial College for work with Jocelyn Field Thorpe, and was awarded a PhD in 1918 and a DSc in 1921.
In 1924, Ingold moved to the University of Leeds where he spent six years as Professor of Organic Chemistry. He returned to London in 1930, and served for 24 years as Head of the chemistry department at University College London, from 1937 until his retirement in 1961.
During his study of alkyl halides, Ingold found evidence for two possible reaction mechanisms for nucleophilic substitution reactions. He found that most secondary and tertiary alkyl halides underwent a two-step mechanism (SN1) while most primary alkyl halides underwent a one-step mechanism (SN2). This conclusion was based on the finding that reactions of most secondary and tertiary alkyl halides with nucleophiles were dependent on the concentration of the alkyl halide only. Meanwhile he discovered that primary alkyl halides, when reacting with nucleophiles, depend on both the concentration of the alkyl halide and the concentration of the nucleophile.
Sir Christopher Ingold received the Longstaff Medal of the Royal Society of Chemistry in 1951, the Royal Medal of the Royal Society in 1952, and was knighted in 1958. The chemistry department of University College London is now housed in the Sir Christopher Ingold building, opened in 1969.
Ingold authored and co-authored 443 papers.
- Shoppee, C. W. (1972). "Christopher Kelk Ingold. 1893-1970". Biographical Memoirs of Fellows of the Royal Society 18: 348–326. doi:10.1098/rsbm.1972.0012.
- Saltzman, M. D. (1986). "The development of physical organic chemistry in the United States and the United Kingdom: 1919-1939, parallels and contrasts". Journal of Chemical Education 63 (7): 588. doi:10.1021/ed063p588. (subscription required)
- Ingold, C. K. (1953). Structure and Mechanism in Organic Chemistry. Ithaca, New York: Cornell University Press. ISBN 0-8014-0499-1.
- Ingold, Christopher K. (1934). "Principles of an Electronic Theory of Organic Reactions". Chemical Reviews 15: 238–274. doi:10.1021/cr60051a003.
- Ingold, C. K. (1941). "Jocelyn Field Thorpe. 1872-1939". Obituary Notices of Fellows of the Royal Society 3 (10): 530–526. doi:10.1098/rsbm.1941.0020. JSTOR 769165.
- Nye, Mary Jo (1994). From Chemical Philosophy to Theoretical Chemistry. University of California Press. pp. 197–198. ISBN 978-0-520-08210-6.
- Saltzman, M. D. (1980). "The Robinson-Ingold controversy: Precedence in the electronic theory of organic reactions". Journal of Chemical Education 57 (7): 484. doi:10.1021/ed057p484.
- Saltzman, Martin D. (1996). "C. K. Ingold's Development of the Concept of Mesomerism". Bulletin for the History of Chemistry 19: 25–32.
Dr. Malmberg's class: K.P.
- Leffek, Kenneth T. (1996). Sir Christopher Ingold: A Major Prophet of Organic Chemistry. Nova Lion Press. ISBN 0-9680674-0-9.
- Ridd, John (December 2008). "Organic Pioneer". Chemistry World 5 (12): 50–53.