Nagata response

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The Nagata reaction is a name reaction in organic chemistry , which was described by Wataru Nagata in 1962 and named after him. The reaction is a hydrocyanation of α , β- unsaturated carbonyl compounds .

Overview reaction

An essential component of the Nagata reaction is the so-called Nagata reagent cyanodiethylaluminum, which can be synthesized by combining triethylaluminum with hydrogen cyanide . Use of this reagent, the addition of a nitrile group (R in the α, β-unsaturated carbonyl compound 1 and R 2 = H , alkyl or aryl group ) after addition of an acid in an inert solvent take place. Suitable solvents are e.g. B. ether , THF and benzene .

Nagata reaction Overview reaction V1.svg

Reaction mechanism

In the first step, the α, β-unsaturated carbonyl compound 1 attacks cyanodiethylaluminum 2 . By shifting electrons , a bond is made between oxygen and aluminum and the position of the nitrile group is changed, as can be seen in compound 3 . Compound 4 is formed with protonation of the double bond and cleavage of the dieethylaluminum ion .

Nagata reaction mechanism V2.svg

application

The Nagata reaction is used to introduce nitrile groups into organic compounds, e.g. B. is useful for the synthesis of natural products . For example, β- amino- α- hydroxycarboxylic acids can be synthesized from the compounds produced with the aid of the Nagata reagent by subsequent hydrolysis , which in turn serve as starting material in the production of β-lactam antibiotics .

Individual evidence

  1. ↑ a b c W. Nagata, M. Yoshioka, S. Hirai: A new hydrocyanation method . In: Tetrahedron Letters . tape 3 , no. 11 , January 1, 1962, p. 461-466 , doi : 10.1016 / S0040-4039 (00) 70493-X .
  2. ↑ a b c d Zerong Wang: Nagata Reaction . In: Comprehensive Organic Name Reactions and Reagents . John Wiley & Sons, Inc., Hoboken, NJ, USA 2010, ISBN 978-0-470-63885-9 , pp. 2007-2010 , doi : 10.1002 / 9780470638859.conrr451 .
  3. ^ W. Nagata, M. Yoshioka, S. Hirai: Alkylaluminum cyanides as potent reagents for hydrocyanation . In: Tetrahedron Letters . tape 7 , no. 18 , January 1, 1966, p. 1913-1918 , doi : 10.1016 / S0040-4039 (00) 76271-X .
  4. ↑ José M. Andrés, María A. Martínez, Rafael Pedrosa, Alfonso Pérez-Encabo: Stereoselective cyanation of chiral α-amino aldehydes by reaction with Nagata's reagent: a route to enantiopure β-amino-α-hydroxy acids . In: Tetrahedron: Asymmetry . tape 12 , no. 2 , February 19, 2001, p. 347-353 , doi : 10.1016 / S0957-4166 (01) 00044-1 .