20842-76-6Relevant articles and documents
Clay montmorillonite K10 catalyzed aldol-type reaction of aldehydes with silyl enol ethers in water
Loh, Teck-Peng,Li, Xu-Ran
, p. 10789 - 10802 (1999)
An environmentally friendly method for the cross aldol reaction of silyl enol ethers and ketene silyl acetal with various aldehydes using montmorillonite K10 is described. Cheap and commercially available montmorillonite K10 can be used without the need of an ion exchange process under solvent-free conditions or in water. Hydrate of aldehydes such as glyoxylic acid can be used directly. Thermal treatment of K10 increased the catalytic activity. The catalytic activity was supposed due to the properties of the structure of K10 and its inherent Bronsted acidity.
Copper Complexes in the Promotion of Aldol Addition to Pyridine-2-carboxaldehyde: Synthesis of Homo- and Heteroleptic Complexes and Stereoselective Double Aldol Addition
álvarez-Miguel, Lucía,Barbero, Héctor,Sacristán-Martín, Adriana,Martín álvarez, José M.,Pérez-Encabo, Alfonso,álvarez, Celedonio M.,García-Rodríguez, Raúl,Miguel, Daniel
, p. 264 - 276 (2018)
CuCl2·2H2O and Cu(ClO4)2·6H2O are able to promote aldol addition of pyridine-2-carboxaldehyde (pyca) with acetone, acetophenone, or cyclohexenone under neutral and mild conditions. The general and simple one-pot procedure for the aldol addition to Cu(II) complexes accesses novel Cu complexes with a large variety of different structural motifs, from which the aldol-addition ligand can be liberated by treatment with NH3. Neutral heteroleptic complexes in which the ligand acts as bidentate, or homoleptic cationic complexes in which the ligand acts as tridentate can be obtained depending on the copper salt used. The key step in these reactions is the coordination of pyca to copper, which increases the electrophilic character of the aldehyde, with Cu(ClO4)2 leading to a higher degree of activation than CuCl2, as predicted by DFT calculations. A regio- and stereoselective double aldol addition of pyca in the reaction of Cu(ClO4)2·6H2O with acetone leads to the formation of a dimer copper complex in which the novel double aldol addition product acts as a pentadentate ligand. A possible mechanism is discussed. The work is supported by extensive crystallographic studies.
Indium trichloride catalysed Mukaiyama aldol reaction in water
Loh, Teck-Peng,Pei, Jian,Cao, Guo-Qiang
, p. 1819 - 1820 (2007/10/03)
In the presence of a catalytic amount of indium(III) chloride (InCl3) (20 mol%), aldehydes react smoothly with ketone trimethylsilyl enol ethers in water to afford the corresponding aldol adducts in good yields.
