Metal-catalyzed asymmetric aldol reactions

Abstract

A reação aldólica é uma das ferramentas mais poderosas e versáteis para a construção de ligações C−C. Tradicionalmente, esta reação foi desenvolvida em sua versão estequiométrica, no entanto, grandes esforços no desenvolvimento de catalisadores quirais para reações aldólicas foram realizados nos últimos anos. Desta forma, neste artigo de revisão, é discutido o desenvolvimento de catalisadores metálicos em reação aldólica do tipo Mukaiyama, reação aldólica redutiva e reação aldólica direta. Além disto, a aplicação destes catalisadores na síntese total de moléculas complexas será abordada.The aldol reaction is one of the most powerful and versatile methods for the construction of C−C bonds. Traditionally, this reaction was developed in a stoichiometric version; however, great efforts in the development of chiral catalysts for aldol reactions were performed in recent years. Thus, in this review article, the development of metal-mediated chiral catalysts in Mukaiyama-type aldol reaction, reductive aldol reaction and direct aldol reaction are discussed. Moreover, the application of these catalysts in the total synthesis of complex molecules is discussed.

Chiral organocatalysts based on lipopeptide micelles for aldol reactions in water

“…Furthermore, in the asymmetric version of the reaction, new stereogenic carbons can be generated with high levels of selectivity. [4][5][6][7][8] In biological systems, aldol reactions are promoted reversibly and stereoselectively by a group of enzymes known as fructose 1,6bisphosphate aldolases, or simply aldolases. 1,4,[9][10][11] Since its first use in 1971, [12][13][14] the amino acid L-proline has showed itself as an efficient and versatile organocatalyst for aldol reactions.…”

Recent Advances in the Catalytic Applications of Chiral Schiff‐Base Ligands and Metal Complexes in Asymmetric Organic Transformations

“…The high enantioselective and high diastereoselective products were obtained. [58] The synthetic usefulness of this reaction is that this reaction can be used to synthesize atorvastatin calcium, which is manipulated to reduce the liver's cholesterol. However, the yield of the reaction was moderate (Scheme 2).…”

“…[62] Followed by their group Several other chiral Schiff base ligands reported for asymmetric Aldol reactions. [58,59] in 2008, when Hiyashi reported the enantioselective Reformatsky reaction of aldehydes 13 and ethyl iodoacetate 14 catalyzed by chiral Schiff base ligand complexes 16 a and 16 b in the presence of dimethyl zinc in an ethereal solvent under the inert condition of Ar-O 2 atmosphere. This process provides a very high enantioselective excess of about 72 % to synthesize chiral β-hydroxy esters 15.…”

An investigation of chiral diamides as organocatalysts in asymmetric aldol reaction

“…After the first asymmetric aldol reaction catalyzed with proline by List et al [3], proline and its derivatives have been investigated as effective asymmetric catalysts in many types of stereoselective synthesis such as aldol reaction, Mannich reaction, Michael reaction, Hanzsch reaction, Strecker reaction, amination, reduction, and oxidation reactions [4]. Asymmetric aldol reaction is one of the most widely investigated reactions due to providing synthetically useful β‐hydroxycarbonyl compounds by CC bond formation [5]. But proline has some drawbacks as organocatalyst in asymmetric aldol reaction such as low solubility, low yields, and low enantioselectivity with aromatic aldehydes.…”