2-Nitrocinnamaldehyde
Encyclopedia
2-Nitrocinnamaldehyde, ortho-nitrocinnamaldehyde or o-nitrocinnamaldehyde is an organic aromatic compound containing a nitro
group
ortho- to the 1-position of cinnamaldehyde
.
in acetic acid, and adding a stoichiometric amount of concentrated nitric acid
at 0-5 °C. Yields are around 36-46% of theoretical.
Nitration
of cinnamaldehyde via acidification of a nitrate
salt with H2SO4
also yields the ortho-nitro compound, however it also yields some of the para-nitro compound, which is generally undesired.
2-Nitrocinnamaldehyde can also be prepared by reacting 2-nitrobenzaldehyde
with acetaldehyde
in a condensation reaction.
to produce indole
and substituted indoles.
Nitro
-Chemistry:*Nitroglycerin, an explosive chemical compound*Nitromethane, the simplest organic nitro compound; also used to fuel high-performance internal-combustion engines*Nitrous oxide, "laughing gas", used in some dental procedures as an anaesthetic...
group
Functional group
In organic chemistry, functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules. The same functional group will undergo the same or similar chemical reaction regardless of the size of the molecule it is a part of...
ortho- to the 1-position of cinnamaldehyde
Cinnamaldehyde
Cinnamaldehyde is the organic compound that gives cinnamon its flavor and odor. This pale yellow viscous liquid occurs naturally in the bark of cinnamon trees and other species of the genus Cinnamomum...
.
Synthesis
2-Nitrocinnamaldehyde can be synthesized by dissolving cinnamaldehyde to a solution of acetic anhydrideAcetic anhydride
Acetic anhydride, or ethanoic anhydride, is the chemical compound with the formula 2O. Commonly abbreviated Ac2O, it is the simplest isolatable acid anhydride and is a widely used reagent in organic synthesis...
in acetic acid, and adding a stoichiometric amount of concentrated nitric acid
Nitric acid
Nitric acid , also known as aqua fortis and spirit of nitre, is a highly corrosive and toxic strong acid.Colorless when pure, older samples tend to acquire a yellow cast due to the accumulation of oxides of nitrogen. If the solution contains more than 86% nitric acid, it is referred to as fuming...
at 0-5 °C. Yields are around 36-46% of theoretical.
Nitration
Nitration
Nitration is a general chemical process for the introduction of a nitro group into a chemical compound. The dominant application of nitration is for the production of nitrobenzene, the precursor to methylene diphenyl diisocyanate...
of cinnamaldehyde via acidification of a nitrate
Nitrate
The nitrate ion is a polyatomic ion with the molecular formula NO and a molecular mass of 62.0049 g/mol. It is the conjugate base of nitric acid, consisting of one central nitrogen atom surrounded by three identically-bonded oxygen atoms in a trigonal planar arrangement. The nitrate ion carries a...
salt with H2SO4
Sulfuric acid
Sulfuric acid is a strong mineral acid with the molecular formula . Its historical name is oil of vitriol. Pure sulfuric acid is a highly corrosive, colorless, viscous liquid. The salts of sulfuric acid are called sulfates...
also yields the ortho-nitro compound, however it also yields some of the para-nitro compound, which is generally undesired.
2-Nitrocinnamaldehyde can also be prepared by reacting 2-nitrobenzaldehyde
2-Nitrobenzaldehyde
2-Nitrobenzaldehyde is an organic aromatic compound containing a nitro group ortho to formyl. 2-Nitrobenzaldehyde once was produced as an intermediate in the synthesis of the popular dye Indigo.-Synthesis:...
with acetaldehyde
Acetaldehyde
Acetaldehyde is an organic chemical compound with the formula CH3CHO or MeCHO. It is one of the most important aldehydes, occurring widely in nature and being produced on a large scale industrially. Acetaldehyde occurs naturally in coffee, bread, and ripe fruit, and is produced by plants as part...
in a condensation reaction.
Uses
2-Nitrocinnamaldehyde can be oxidized to 2-nitrocinnamic acid which can be used in the Baeyer-Emmerling indole synthesisBaeyer-Emmerling indole synthesis
The Baeyer-Emmerling indole synthesis is a method for synthesizing indole from a ortho-nitrocinnamic acid and iron powder in strongly basic solution. This reaction was discovered by Adolf von Baeyer and A. Emmerling in 1869....
to produce indole
Indole
Indole is an aromatic heterocyclic organic compound. It has a bicyclic structure, consisting of a six-membered benzene ring fused to a five-membered nitrogen-containing pyrrole ring. Indole is a popular component of fragrances and the precursor to many pharmaceuticals. Compounds that contain an...
and substituted indoles.