Practical Enantioselective Reduction of Ketones Using Oxazaborolidine Catalysts Generated In Situ from Chiral Lactam Alcohols

doi:10.3390/molecules23102408

Paper

Practical Enantioselective Reduction of Ketones Using Oxazaborolidine Catalysts Generated In Situ from Chiral Lactam Alcohols

Published Sep 20, 2018 · Y. Kawanami, Ryo C. Yanagita

Molecules : A Journal of Synthetic Chemistry and Natural Product Chemistry

Q1 SJR score

11

Citations

0

Influential Citations

Open Access PDF Full text Semantic Scholar

Abstract

Oxazaborolidine catalyst (CBS catalyst) has been extensively used for catalytic borane reduction with a predictable absolute stereochemistry and high enantioselectivity. However, the use of isolated CBS catalyst sometimes has the drawback of low reproducibility due to the aging of the CBS catalyst during storage. Therefore, we investigated a more reliable and practical method for the reduction of a variety of ketones including challenging substrates, primary aliphatic ketones, α,β-enones, and trifluoromethyl ketones. This review surveys the developments in borane reduction using oxazaborolidine catalysts generated in situ from chiral lactam alcohols and borane.

Study Snapshot

Oxazaborolidine catalysts generated in situ from chiral lactam alcohols and borane provide a more reliable and practical method for enantioselective reduction of various ketones.

PopulationOlder adults (50-71 years)

Sample size24

MethodsObservational

OutcomesBody Mass Index projections

ResultsSocial networks mitigate obesity in older groups.

Sign up to use Study Snapshot

Consensus is limited without an account. Create an account or sign in to get more searches and use the Study Snapshot.

Create an account

Paper

Practical Enantioselective Reduction of Ketones Using Oxazaborolidine Catalysts Generated In Situ from Chiral Lactam Alcohols

Sign up to use Study Snapshot

References

Effect of BF3 on the enantioselective reduction of trifluoromethyl ketones using a chiral lactam alcohol with borane

BF3-THF enhances enantioselectivity and yield in the reduction of reactive trifluoromethyl ketones at room temperature, reaching up to 90% ee.

Enantioselective reduction of trifluoromethyl ketones using an oxazaborolidine catalyst generated in situ from a chiral lactam alcohol

The oxazaborolidine catalyst, generated from chiral lactam alcohol and borane, effectively reduces highly reactive trifluoromethyl ketones at room temperature with high enantioselectivities up to 86%.

Rational electronic tuning of CBS catalyst for highly enantioselective borane reduction of trifluoroacetophenone.

Electronically tuned-CBS catalyst with BH(3) effectively reduces trifluoroacetophenone to chiral alcohol up to 90% ee, with enantioselectivity highly correlated to differential orbital energies.

Enantioselective synthesis of cyclic, quaternary oxonitriles.

This study presents a stereoselective synthesis of quaternary oxonitriles using a Claisen rearrangement strategy, enabling the generation of hindered centers with enantiomeric ratios typically greater than 9:1.

Enantioselective, organocatalytic reduction of ketones using bifunctional thiourea-amine catalysts.

This study demonstrates enantioselective organocatalytic reduction of prochiral ketones to enantioenriched secondary alcohols using catecholborane and bifunctional thiourea-amine catalysts, with asymmetric induction arising from the complexation between the borane and

Enantioselective Reduction of Prochiral Ketones using Spiroborate Esters as Catalysts.

Spiroborate esters effectively catalyze asymmetric borane reduction of prochiral ketones, resulting in highly optically active alcohols with up to 99% ee.

Citations

Investigation Towards the Asymmetric CBS‐Catalysed Reduction of Aryl Methyl Ketones with Electrochemically in Situ Generated BH3

Alternative Approach to the Large-Scale Synthesis of the Densely Functionalized Pyrrolidone BMT-415200

Oxathiaborolium-catalyzed enantioselective [2 + 2] cycloadditions.

Chiral Aminoalcohols and Squaric Acid Amides as Ligands for Asymmetric Borane Reduction of Ketones: Insight to In Situ Formed Catalytic System by DOSY and Multinuclear NMR Experiments

Oxathiaborolium-Catalyzed Enantioselective [4 + 2] Cycloaddition and Its Application in Lewis Acid Coordinated and Chiral Lewis Acid Catalyzed [4 + 2] Cycloaddition.

Chiral phosphoric acid catalyzed asymmetric transfer hydrogenation of bulky aryl ketones with ammonia borane

Bimetallic Radical Redox-Relay Catalysis for the Isomerization of Epoxides to Allylic Alcohols.