Dibenzylideneacetone

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Dibenzylideneacetone
Dibenzylideneacetone.png
Dibenzylideneacetone-3D-balls.png
DBAxtals.JPG
Names
IUPAC name
(1E, 4E)-1,5-Diphenylpenta-1,4-dien-3-one
Other names
Dibenzalacetone
Identifiers
538-58-9 undefined YesY
35225-79-7 (E,E) N
115587-57-0 (E,Z) N
58321-78-1 (Z,Z) N
ChEMBL ChEMBL17201 (E,E) N
ChemSpider 86113 undefined N
555548 (E,E) N
1266463 (E,Z) N
1266462 (Z,Z) N
Jmol 3D model undefined: Interactive image
(E,E): Interactive image
(E,Z): Interactive image
(Z,Z): Interactive image
PubChem 95417 undefined
640180 (E,E)
1549622 (E,Z)
1549621 (Z,Z)
UNII 9QXO7BCY9L (E,E) N
N4SH2VDI6Y (E,Z) N
5L4OCE3E5U (Z,Z) N
Properties
C17H14O
Molar mass 234.29 g/mol
Appearance Yellow solid
Melting point *Aldrich 110-111 °C (trans, trans isomer)
  • Merck 60 °C (cis, trans isomer)
Boiling point 130 °C (266 °F; 403 K) (cis, cis isomer) *Merck
soluble
Hazards
Main hazards Irritant
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N verify (what is YesYN ?)
Infobox references
Drying dibenzalacetone

Dibenzylideneacetone or dibenzalacetone, often abbreviated dba, is an organic compound with the formula C17H14O. It is a pale-yellow solid insoluble in water, but soluble in ethanol. Dibenzylideneacetone is used as a component in sunscreens and as a ligand in organometallic chemistry.

Preparation[edit]

The compound can be prepared in the laboratory through condensation of benzaldehyde and acetone with sodium hydroxide in a water/ethanol medium with the exclusive formation of the trans, trans isomer (melting point 110–111 °C).[1]

Dibenzalacetone synthesis

This reaction is frequently encountered in organic chemistry education as a laboratory procedure. The conversion proceeds via the intermediacy of benzylideneacetone.

Reactions and derivatives[edit]

Prolonged exposure to sunlight converts the compound in a [2+2] cycloaddition to a mixture of four cyclobutane isomers.[2]

Dibenzylideneacetone is a component of the catalyst tris(dibenzylideneacetone)dipalladium(0). It is a labile ligand that is easily displaced by triphenylphosphine, hence it serves a useful entry point into palladium(0) chemistry.

References[edit]

  1. ^ Conard, C. R.; Dolliver, M. A. (1943). "Dibenzalacetone". Org. Synth.  ; Coll. Vol., 2, p. 167 
  2. ^ Rao, G. N.; Janardhana, C.; Ramanathan, V.; Rajesh, T.; Kumar, P. H. (November 2006). "Photochemical Dimerization of Dibenzylideneacetone. A Convenient Exercise in [2+2] Cycloaddition Using Chemical Ionization Mass Spectrometry". J. Chem. Educ. 83 (11): 1667. doi:10.1021/ed083p1667.