Mukaiyama s classic catalytic asymmetric aldol reaction with enolsilanes has been improved upon over the years; now new approaches to the reaction have been developed. Those reviewed here are the use of new transition metal based catalysts for the aldol reaction using silyl enolates, the use of other O-silylated nucleophiles, tin-modified or even unmodified ketones as substrates, and the use of...

Asymmetric aldol reactions of α-amino acid derivatives via memory of chirality were developed. Chiral oxazolidones with contiguous tetra- and trisubstituted chiral centers were obtained in 78-94% ee by the asymmetric aldol reaction followed by intramolecular acylation.

4.2.8. Reductive Coupling 3109 5. Reaction of Aromatic Compounds 3110 5.1. Electrophilic Substitutions 3110 5.2. Radical Substitution 3111 5.3. Oxidative Coupling 3111 5.4. Photochemical Reactions 3111 6. Reaction of Carbonyl Compounds 3111 6.1. Nucleophilic Additions 3111 6.1.1. Allylation 3111 6.1.2. Propargylation 3120 6.1.3. Benzylation 3121 6.1.4. Arylation/Vinylation 3121 6.1.5. Alkynylat...

Ieodomycin B, which shows in vitro antimicrobial activity, was isolated from a marine Bacillus species. A novel asymmetric total synthetic approach to ieodomycin B using commercially available geraniol was achieved. The approach involves the generation of 1,3-trans-dihydroxyl at C-3 and C-5 positions via a Crimmins-modified Evans aldol reaction and a chelation-controlled Mukaiyama aldol reactio...

Cyanosilylation, aldol coupling and asymmetric Henry reactions were carried out with L- D-valmet ligands in different configurations: i) coordinated to sodium ions, as organocatalysts, week base properties, ii) complexes copper(II), homogeneous catalysts, iii) immobilized copper(II) onto graphene oxide (GO) heterogeneous catalysts. For the reaction of benzaldehyde nitromethane water these affor...

Key words (+)-malettinin C - E asymmetric organocatalytic aldol reaction Buchner ring expansion Dess–Martin oxidation oxidative dearomatization

BACKGROUND The diastereoselectivity of a vinylogous Mukaiyama aldol reaction of a series of N-substituted 4-oxy-2-trimethylsilyloxypyrroles with a tartrate-based aldehyde has been explored as a model reaction for castanospermine synthesis. RESULTS The study has revealed that the reaction is sensitive to the nature of the combination of N- and 4-oxy substituents. With a N-PMB or N-Bn and 4-met...

Aldol reactions belong to the most frequently used C-C bond forming transformations utilized particularly for the construction of complex structures. The selectivity of these reactions depends on the geometry of the intermediate enolates. Here, we have reacted octyl pentafluoro-λ6-sulfanylacetate with substituted benzaldehydes and acetaldehyde under the conditions of the silicon-mediated Mukaiy...

[structure: see text] Non-aldol aldol rearrangement of the epoxy silyl ether 13b afforded the expected anti methyl ketone 14, while the diastereomeric epoxy silyl ether 13a afforded the syn methyl ketone 8b via an unprecedented syn hydride migration. Calculations suggest that this unusual reaction proceeds via the carbocation, which cannot easily rotate due to steric hindrance.