Multicomponent synthesis of chiral sulfinimines
Caroline Roe1, Heather Hobbs, Robert A Stockman
1School of Chemistry, University of Nottingham, Nottingham, UK.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|January 29, 2011
Summary
New chiral sulfinimine synthesis utilizes recyclable oxathiozolidine-S-oxide templates. This efficient four-component coupling method offers high enantiomeric excesses and uses readily available starting materials.
Area of Science:
- Organic Chemistry
- Asymmetric Synthesis
- Sulfur Chemistry
Background:
- Chiral sulfinimines are valuable synthetic intermediates.
- Efficient and enantioselective methods for their synthesis are highly sought after.
- Existing methods may suffer from limited substrate scope or harsh reaction conditions.
Purpose of the Study:
- To develop novel oxathiozolidine-S-oxide templates for chiral sulfinimine synthesis.
- To establish a versatile four-component coupling protocol utilizing these templates.
- To achieve high enantioselectivity and yields in the synthesis of diverse chiral sulfinimines.
Main Methods:
- Development and synthesis of two oxathiozolidine-S-oxide templates from commodity chemicals.
- Application of a four-component coupling reaction employing the developed templates.
- Purification and characterization of the synthesized chiral sulfinimines.
Main Results:
- Successful synthesis of a wide range of chiral sulfinimines with high enantiomeric excesses.
- The oxathiozolidine-S-oxide templates are synthesized in high yields within three steps.
- The templates demonstrate excellent recoverability and recyclability, enhancing process sustainability.
Conclusions:
- The developed oxathiozolidine-S-oxide templates and four-component coupling protocol provide an efficient route to chiral sulfinimines.
- The method is cost-effective due to the use of cheap starting materials and recyclable templates.
- This approach offers a sustainable and scalable solution for accessing enantiomerically enriched sulfinimines.
More Related Videos
06:31Highly Stereoselective Synthesis of 1,6-Ketoesters Mediated by Ionic Liquids: A Three-component Reaction Enabling Rapid Access to a New Class of Low Molecular Weight Gelators
Published on: November 27, 2015
07:50Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Related Concept Videos
02:26Preparation and Reactions of Sulfides
Sulfides are the sulfur analog of ethers, just as thiols are the sulfur analog of alcohol. Like ethers, sulfides also consist of two hydrocarbon groups bonded to the central sulfur atom. Depending upon the type of groups present, sulfides can be symmetrical or asymmetrical. Symmetrical sulfides can be prepared via an SN2 reaction between 2 equivalents of an alkyl halide and one equivalent of sodium sulfide.
02:30Chirality at Nitrogen, Phosphorus, and Sulfur
Chirality is most prevalent in carbon-based tetrahedral compounds, but this important facet of molecular symmetry extends to sp3-hybridized nitrogen, phosphorus and sulfur centers, including trivalent molecules with lone pairs. Here, the lone pair behaves as a functional group in addition to the other three substituents to form an analogous tetrahedral center that can be chiral.
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...
01:23Amines to Sulfonamides: The Hinsberg Test
The Hinsberg test is a method to identify primary, secondary and tertiary amines, named after its pioneer, Oscar Hinsberg. Here, amines are treated with benzenesulfonyl chloride, also known as the Hinsberg reagent, in the presence of an excess of aqueous base, followed by acidification. Based on the nature of the amines, different changes are observed.
Generally, a primary amine reacts with the Hinsberg reagent to produce an N-substituted benzenesulfonamide. The electron-withdrawing sulfonyl...
Generally, a primary amine reacts with the Hinsberg reagent to produce an N-substituted benzenesulfonamide. The electron-withdrawing sulfonyl...
02:05Prochirality
The concept of prochirality leads to the nomenclature of the individual faces of a molecule and plays a crucial role in the enantioselective reaction. It is a concept where two or more achiral molecules react to produce chiral products. A typical process is the reaction of an achiral ketone to generate a chiral alcohol. Here, the achiral reactant reacts with an achiral reducing agent, sodium borohydride, to generate an equimolar mixture of the chiral enantiomers of the product. For example, an...
01:16Aldehydes and Ketones with Amines: Imine and Enamine Formation Overview
Primary amines react with carbonyl compounds—aldehydes and ketones—to generate imines. Imines consist of a C=N double bond and are named Schiff bases after its discoverer—the German chemist Hugo Schiff. On the other hand, secondary amines react with carbonyl compounds to give enamines. In enamines, the presence of a C=C double bond adjacent to the nitrogen atom leads to the delocalization of the lone pair.
02:23SN2 Reaction: Stereochemistry
In an SN2 reaction, the nucleophilic attack on the substrate and departure of the leaving group occurs simultaneously through a transition state. As the nucleophile approaches the substrate from the back-side, the configuration of the substrate carbon changes from tetrahedral to trigonal bipyramidal and then back to tetrahedral, leading to an inversion in the configuration of the product.
If the substrate is an achiral molecule at the α-carbon, the inversion of configuration is not observed.
If the substrate is an achiral molecule at the α-carbon, the inversion of configuration is not observed.