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The catalytic asymmetric construction of chiral quaternary stereocenters is a continual area of research for organic chemists. In this sense, when a chlorine atom is introduced to a quaternary stereocenter, the synthetic difficulty of the resulting molecule increases along with its significance. This is true not only because of the intrinsic interest in such chlorinated molecules but also because they are highly valuable chiral building blocks in organic synthesis, as they can be converted into more complex molecules by a SN2 displacement reaction. Among the different strategies to create chlorinated quaternary stereogenic centers, organocatalysis has played a pivotal role over the past decade. In this review, a comprehensive analysis of such organocatalyzed transformations with a focus on the a-chlorination of carbonyl compounds is presented. [ABSTRACT FROM AUTHOR]

Bifunctional chiral 2-aminobenzimidazole derivatives 1 and 2 catalyze the enantioselective stereodivergent α-chlorination of β-ketoesters and 1,3-diketone derivatives with up to 50% ee using N-chlorosuccinimide (NCS) or 2,3,4,4,5,6-hexachloro-2,5-cyclohexadien-1-one as electrophilic chlorine sources. [ABSTRACT FROM AUTHOR]

The use of a trans-cyclohexanediamine benzimidazole derivative as a hydrogen-bond catalyst for the electrophilic amination of cyclic 1,3-dicarbonyl compounds is herein presented. High yields and enantioselectivities varying from moderate to excellent are generally obtained using mild reaction conditions and as low as 1 mol% of catalyst loading. [ABSTRACT FROM AUTHOR]

This paper reviews the present state of the catalytic enantioselective Reformatsky reaction. Advancements in asymmetric versions of this reaction have recently led to a considerable extension of its scope and applicability, principally due to the use of highly active chiral ligands and very specific reaction conditions. [ABSTRACT FROM AUTHOR]

A wide variety of chiral succinimides have been prepared in high yields and enantioselectivities by asymmetric conjugate addition of 1,3-dicarbonyl compounds to maleimides under very mild reaction conditions using a bifunctional benzimidazole-derived organocatalyst. Computational and NMR studies support the hydrogen-bonding activation role of the catalyst and the origin of the stereoselectivity of the process. [ABSTRACT FROM AUTHOR]