Schiff Bases of aliphatic aldehyde get readily polymerized in nature and are unstable whereas Schiff bases of aromatic aldehyde
are more stable due to involvement in the conjugation system.
Furfural, an aromatic aldehyde
, is also a renewable resource obtained as an agricultural waste product.
This might be pigskin has small amount of the molecular absorption for the functional group of carbonyl, amide group, or aromatic aldehyde
A mixture of equimolar amounts of flavanones and aromatic aldehyde
and a few drops of piperidine was allowed to react at 150oC and E-3 arylidene flavanone was obtained in good yield without any purification.
Equimolar quantities of benzil and substituted aromatic aldehyde
, ammonium acetate were dissolved in glacial acetic acid and refluxed for 3-5 hours.
A mixture of an aromatic aldehyde
(1 mmol), benzil/benzoin (1mmol), ammonium acetate (2 mmol) and tannic acid (7.
Compounds containing an azomethine group (-CH=N-) are known as Schiff bases (SBs) which are usually prepared by the condensation of an aromatic aldehyde
or ketone with primary amines .
Due to the availability of the starting material and comparative ease with which reaction can be run, one of the most recurrently used means of establishing the flavonol nucleus involves the Claisen-Schmidt reaction flanked by 2-hydroxy acetophenone and aromatic aldehyde
In a 250 mL pre-backed two-necked flask supplied with magnetic stirrer, 4 mL (43 mmol) of aniline in 20 mL of dried toluene was mixed with an equimolar amount of aromatic aldehyde
in 20 mL of toluene.
03 mole of appropriate aromatic aldehyde
is dissolved in 30 mL of CHCl3.
The reaction was a mixture of aromatic aldehyde
(1mmol), malononitrile (132mg, 2mmol), substituted thiophenol (1mmol), phosphotungstic acid (2mol %), CTAB (10 mol %) and water (5 mL) in a 50mL round bottom flask.
4,6-Diarylpyrimidin-2(1H)-one derivatives have been synthesized from three-component reaction of aromatic aldehyde
derivatives, acetophenone, and urea (thiourea) in the presence of BrAnsted acidic ionic liquids such as triethylammonium hydrogensulfate, N-methyl-2-pyrrolidonium dihydrogen phosphate, 3-methyl-1-sulfonic acid imidazolium chloride, N-methyl-2-pyrrolidonium hydrogensulfate, and 2-pyrrolidonium hydrogensulfate as catalyst under thermal solvent-free conditions in excellent yields.