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The Dakin-West reaction is a chemical reaction that transforms an amino-acid into an amino-ketone using a acid anhydride and a base, typically pyridine. A chemical reaction is a process that always results in the interconversion of Chemical substances The substance or substances initially involved in a chemical reaction are called In Chemistry, an amino acid is a Molecule containing both Amine and Carboxyl Functional groups In Biochemistry, this Amines are Organic compounds and Functional groups that contain a basic Nitrogen Atom with a Lone pair. A ketone (pronounced as key tone) is either the Functional group characterized by a Carbonyl group (O=C linked to two other Carbon atoms or An acid anhydride is an Organic compound that has two Acyl groups bound to the same Oxygen atom Pyridine is a Chemical compound with the formula C5[[Hydrogen H5]] N. [1][2][3] It is named for Henry Drysdale Dakin (1880–1952) and Randolph West (1890–1949). Henry Drysdale Dakin (1880 - 1952 was an English Chemist. He was born in London as the youngest of 8 children to a family of steel merchants from Year 1880 ( MDCCCLXXX) was a Leap year starting on Thursday (link will display the full calendar of the Gregorian calendar (or a Leap year Year 1952 ( MCMLII) was a Leap year starting on Tuesday (link will display full calendar of the Gregorian calendar. Year 1890 ( MDCCCXC) was a Common year starting on Wednesday (link will display the full calendar of the Gregorian calendar (or a Common Year 1949 ( MCMXLIX) was a Common year starting on Saturday (link will display the full calendar of the Gregorian calendar. Of special note, the amino-ketone product is always racemic. In Chemistry, a racemic mixture, or racemate, is one that has equal amounts of left- and right-handed enantiomers of a chiral

The Dakin-West reaction

With pyridine as a base and solvent, refluxing conditions are required. A solvent is a liquid or gas that dissolves a solid liquid or gaseous Solute, resulting in a Solution. [4] However, with the addition of 4-dimethylaminopyridine (DMAP) as a catalyst, the reaction can take place at room temperature. DMAP redirects here For the cyanide antidote see 4-Dimethylaminophenol 4-Dimethylaminopyridine (DMAP is a nucleophilic catalyst which catalyzes [5]

With some acids, this reaction can take place even in the absence of an α-amino group.

This reaction should not be confused with the Dakin reaction. The Dakin reaction is the Chemical reaction of Phenolic Aldehydes (or Ketones with Hydrogen peroxide to form bisphenols and Carboxylic acids

Reaction mechanism

The reaction mechanism involves the acylation and activation of the acid 1 to the mixed anhydride 3. The amide will serve as a nucleophile for the cyclization forming the azlactone 4. Deprotonation and acylation of the azlactone forms the key carbon-carbon bond. Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 Subsequent ring-opening of 6 and decarboxylation give the final amino-ketone product. Decarboxylation is any Chemical reaction in which a Carboxyl group (-COOH is split off from a compound as Carbon dioxide (CO2 [6][7]

The mechanism of the Dakin-West reaction

References

  1. ^  (a) Dakin, H. D.; West, R. Henry Drysdale Dakin (1880 - 1952 was an English Chemist. He was born in London as the youngest of 8 children to a family of steel merchants from J. Biol. Chem. 1928, 78, 91. (b) Dakin, H. D. ; West, R. J. Biol. Chem. 1928, 78, 745. (c) Dakin, H. D. ; West, R. J. Biol. Chem. 1928, 78, 757.
  2. ^  Wiley, R. H. J. Org. Chem. 1947, 12, 43-46. The Journal of Organic Chemistry (abbreviated as J Org Chem or JOC) is a Scientific journal for original contributions of fundamental (doi:10.1021/jo01165a006)
  3. ^  Buchanan, G. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document. L. Chem. Soc. Rev. 1988, 17, 91-109. Chemical Society Reviews is a peer-reviewed Scientific journal publishing review articles on topics of current interest in the chemical (Review)
  4. ^  Wiley, R. H. ; Borum, O. H. Organic Syntheses, Coll. Organic Syntheses is a Scientific journal that since 1921 has provided the Chemistry community with annual collections of detailed and checked procedures Vol. 4, p. 5 (1963); Vol. 33, p. 1 (1953). (Article)
  5. ^  Hoefle, G. ; Steglich, W. ; Vorbrueggen, H. Angew. Chem. Int. Ed. Engl. 1978, 17, 569. Angewandte Chemie is a weekly Peer-reviewed Chemistry journal that covers all disciplines of chemistry
  6. ^  Knorr, R. ; Huisgen, R. Ber. 1970, 103, 2598. See also Anales de Química Bulletin des Sociétés Chimiques Belges Bulletin de la Société Chimique de France
  7. ^  Allinger, N. et al. J. Org. Chem. 1974, 39, 1730. The Journal of Organic Chemistry (abbreviated as J Org Chem or JOC) is a Scientific journal for original contributions of fundamental (doi:10.1021/jo00925a029)
A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.
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