Claisen–Schmidt condensation

In organic chemistry, the Claisen–Schmidt condensation is the reaction between an aldehyde or ketone having an α-hydrogen with an aromatic carbonyl compound lacking an α-hydrogen. It can be considered as a specific variation of the aldol condensation. This reaction is named after two of its pioneering investigators Rainer Ludwig Claisen and J. Gustav Schmidt, who independently published on this topic in 1880 and 1881.[1][2][3] An example is the synthesis of dibenzylideneacetone ((1E, 4E)-1,5-diphenylpenta-1,4-dien-3-one).[4]

Dibenzalacetone synthesis

Quantitative yields in Claisen–Schmidt reactions have been reported in the absence of solvent using sodium hydroxide as the base and plus benzaldehydes.[5] Because the enolizable nucleophilic carbonyl compound and the electrophilic carbonyl compound are two different chemicals, the Claisen–Schmidt reaction is an example of a crossed aldol process.

References

edit
  1. ^ Claisen, L.; Claparède, A. (1881). "Condensationen von Ketonen mit Aldehyden" [Condensations of ketones with aldehydes]. Berichte der Deutschen Chemischen Gesellschaft. 14 (1): 2460–2468. doi:10.1002/cber.188101402192.
  2. ^ Schmidt, J. G. (1881). "Ueber die Einwirkung von Aceton auf Furfurol und auf Bittermandelöl in Gegenwart von Alkalilauge" [On the effect of acetone on furfural and on bitter almond oil (benzaldehyde) in the presence of alkali hydroxides]. Berichte der Deutschen Chemischen Gesellschaft. 14 (1): 1459–1461. doi:10.1002/cber.188101401306.
  3. ^ March, J. (1985). Advanced Organic Chemistry: Reactions, Mechanisms and Structure (3rd ed.). Wiley Interscience. p. 1145. ISBN 0-471-85472-7.
  4. ^ Hull, L. A. (February 2001). "The Dibenzalacetone Reaction Revisited". J. Chem. Educ. 78 (2): 226. Bibcode:2001JChEd..78..226H. doi:10.1021/ed078p226.
  5. ^ Rahman A. F. M. Motiur, Ali Roushown, Jahng Yurngdong, Kadi Adnan A. (2012). "A Facile Solvent Free Claisen-Schmidt Reaction: Synthesis of α,α′-bis-(Substituted-benzylidene)cycloalkanones and α,α′-bis-(Substituted-alkylidene)cycloalkanones". Molecules. 17 (1): 571–583. doi:10.3390/molecules17010571. PMC 6269007. PMID 22231494.{{cite journal}}: CS1 maint: multiple names: authors list (link)