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...

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. This 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...

The enantioselective total synthesis of pironetin has been achieved in 11 steps from known aldehyde 2. The synthesis relies on the formation of 5 out of 6 stereocenters through titanium mediated iterative aldol reactions. Key steps in this synthesis include an acetal aldol reaction to establish the stereochemistry at C8 and C9, an acetate aldol reaction, and "Evans" syn aldol reaction.

Thioamides are the preferred pronucleophiles for direct catalytic asymmetric aldol reactions in the context of soft Lewis acid/hard Brønsted base cooperative catalysis. In-depth investigation of this proton-transfer catalysis, which is virtually in equilibrium, revealed that the prominence of the retro-aldol reaction depended on the substrate combination. The retro-aldol reaction is a serious i...

3-methyl-1-sulfonic acid imidazolium tetrachloroferrate {[Msim]FeCl4} as an efficient sulfur catalyst was prepared and applied, as an efficient catalyst, for the cross-aldol condensation reaction between cycloalkanones and arylaldehydes to give α,αʹ- bis(arylidene)cycloalkanones in high yields and short reaction times at 75 °C under solvent-free conditions. 3-methyl-1-sulfonic acid imidazolium...

chromanone derivatives demonstrate remarkable cytotoxity against a varieties of cancer cell lines. novel 9-[hydroxy(substitutedphenyl)methyl]-2,2-dimethyl-2,3,8,9- tetrahydro-4h,10h-pyrano[2,3-f]chromene-4,10-diones as glyasperin analogues were synthesized in four steps from known 4-chromone 1. the key step was the preparation of chromane dione 5a by regioselective intramolecular cyclization re...

Key words (+)-bufogargarizin B - [5+2] cycloaddition Mukaiyama hydration retro-aldol-aldol reaction Suzuki–Miyaura coupling

An unexpected yet disciplined course of catalytic Mukaiyama-aldol reaction instead of the expected vinylogous Mukaiyama-aldol reaction has been observed for the reaction of silyloxyfuran with various aldehydes under Lewis acid catalytic control in water-containing solvents.

An asymmetric proline catalyzed aldol reaction with a-thioacetal aldehydes has been developed. Thioacetal bearing aldehydes readily participate as electrophilic cross-aldol partners with a broad range of aldehyde and ketone donors. High levels of reaction efficiency as well as diastereoand enantiocontrol are observed in the production of anti-aldol adducts. q 2004 Elsevier Ltd. All rights reser...