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Barton–McCombie Deoxygenation
The Barton–McCombie deoxygenation is an organic reaction in which a hydroxy functional group in an organic compound is replaced by a hydrogen to give an alkyl group. It is named after British chemists Sir Derek Harold Richard Barton and Stuart W. McCombie. This deoxygenation reaction is a radical substitution. In the related Barton decarboxylation the reactant is a carboxylic acid. Mechanism The reaction mechanism consists of a catalytic radical initiation step and a propagation step. The alcohol (1) is first converted into a reactive carbonothioyl intermediate such as a thionoester or xanthate 2. Heating of AIBN results in its homolytic cleavage, generating two 2-cyanoprop-2-yl radicals 9 which each abstract a proton from tributylstannane 3 to generate tributylstannyl radicals 4 and inactive 10. The tributyltin radical abstracts the xanthate group from 2 by attack of 4 at the sulfur atom with concurrent homolytic cleavage of the C-S π bond. This leaves a carbon center ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Derek Harold Richard Barton
Sir Derek Harold Richard Barton (8 September 1918 – 16 March 1998) was an English organic chemist and Nobel Prize laureate for 1969. Education and early life Barton was born in Gravesend, Kent, to William Thomas and Maude Henrietta Barton (''née'' Lukes). He attended Gravesend Grammar School (1926–29), The King's School, Rochester (1929–32), Tonbridge School (1932–35) and Medway Technical College (1937–39). In 1938 he entered Imperial College London, where he graduated in 1940 and obtained his Doctor of Philosophy, PhD degree in Organic Chemistry in 1942. Career and research From 1942 to 1944 Barton was a government research chemist, then from 1944 to 1945 he worked for Albright and Wilson in Birmingham. He then became Assistant Lecturer in the Department of Chemistry of Imperial College, and from 1946 to 1949 he was Imperial Chemical Industries, ICI Research Fellow. During 1949 and 1950 he was visiting lecturer in natural products chemistry at Harvard University, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
