Aldol Condensation Reactions Effectively Catalysed by Lewis Acid

Aldol condensation versus conjugate addition: intramolecular cyclization using a combination of Lewis acid and 1,2-diol.

The reactivity of 3-substituted 4-methyl-4-(3-oxobutyl)-2-cyclohexen-1-ones (1) in the presence of a combination of a Lewis acid and a 1,2-diol was studied. The results suggest several factors that influence 6-membered ring formation, including two types of intramolecular aldol reaction and intramolecular 1,4-addition, due to the C3-substituent, Lewis acid, and the presence of diol. In this stu...

Aldol type Condensation Reactions of Acyl Ketene Dithioacetals

Primary amine-metal Lewis acid bifunctional catalysts: the application to asymmetric direct aldol reactions.

The first example of metal Lewis acid-primary amine bifunctional cooperative catalyst derived from primary amino acids was developed, and it was found to catalyze aldol reactions of cyclic ketones highly efficiently with very good to excellent stereoselectivities.

Synthesis of functionalized tryptamines by Brønsted acid catalysed cascade reactions.

An original synthetic protocol has been developed for the preparation of highly functionalized tryptamines from 2-hydroxycyclobutanone and secondary arylamines via a solvent-free Brønsted acid catalysed two-step reaction sequence.

Organic Synthesis: Aldol Condensation Reaction

In an "aldol addition" reaction an enol or enolate of an aldehyde or ketone reacts with a second aldehyde or ketone forming a new carbon-carbon bond which makes the aldol reaction an important reaction for organic synthesis. Originally, the aldol reaction used ethanal (see below) and therefore the product contained both an aldehyde and an alcohol functional group; thus it became known as the al...