Knoevenagel Reaction

Knoevenagel reaction

[kə′nē·və‚näg·əl rē‚ak·shən]
(organic chemistry)
The condensation of aldehydes with compounds containing an activated methylene (=CH2) group.

Knoevenagel Reaction

 

the condensation of aldehydes or ketones with compounds containing an active methylene group in the presence of bases, resulting in the formation of ethylene derivatives. For example, a derivative of cinnamic acid (III) is obtained during the condensation of benzaldehyde (I) with the diethyl ester of malonic acid (II) in the presence of piperidine:

The Knoevenagel reaction is widely used in the laboratory for organic synthesis and in the chemical-pharmaceutical and perfume industries. The German scientist E. Knoevenagel discovered the reaction in 1896.

REFERENCE

Surrey, A. Spravochnik po organicheskim reaktsiiam. Moscow, 1962. (Translated from English.)
Mentioned in ?
References in periodicals archive ?
The Knoevenagel reaction was carried out smoothly under the optimum conditions with the yields of 80-99% within short time.
Liu, The Knoevenagel Reaction in Water Catalyzed by Zwitterionic Liquids, Monatsh.
Hayashi, Use of Isopropyl Alcohol as a Solvent in Ti(O-i-Pr)4-Catalyzed Knoevenagel Reactions, Tetrahedron, 61, 7981 (2005).
4]OAc by modified Knoevenagel reaction using microwave irradiation, as indicated in Scheme 1 and Table 3.
Microwave-assisted ammonium formate-mediated Knoevenagel reaction under solvent-free conditions --a green method for C-C bond formation.
60], were synthesized using Knoevenagel reactions between (E)-4-((4-(4-(dimethyl amine)styryl)phenyl) (phenyl)amino) benzaldehyde 9 and cyanoacetic acid, also using a 1,3-dipolar cycloaddition reaction with N-octylglycine and fullerene [C.