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Updated: Apr 11, 2026

Synthesis of a Thiol Building Block for the Crystallization of a Semiconducting Gyroidal Metal-sulfur Framework
Published on: April 9, 2018
Reductive Alkylation of Arenes by a Thiol-Based Multicomponent Reaction
1Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
A new method allows direct introduction of alkyl groups into aromatic compounds using a simple, one-pot reaction. This versatile electrophilic aromatic substitution is efficient and compatible with various functional groups.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Aromatic compounds are fundamental building blocks in chemistry.
- Efficient methods for functionalizing aromatic rings are crucial for synthesizing diverse molecules.
Purpose of the Study:
- To develop a simple, highly chemo- and regioselective method for introducing primary alkyl substituents into aromatic compounds.
- To establish a versatile one-pot protocol compatible with various functional groups and reaction conditions.
Main Methods:
- The method utilizes an electrophilic aromatic substitution of an aldehyde, promoted by a thiol.
- The reaction produces 1-(alkylthio)alkylarenes, which can be further reduced in situ or modified.
- This multicomponent reaction allows for the direct incorporation of aromatic and aliphatic alkyl groups.
Main Results:
- A facile and selective method for alkylating aromatic compounds was successfully developed.
- The protocol enables the introduction of both linear and branched aliphatic alkyl groups.
- The one-pot reaction is tolerant to air, water, and various functional groups, enhancing its practicality.
Conclusions:
- The developed method offers a straightforward and efficient approach for alkylating aromatic compounds.
- This versatile synthetic strategy expands the toolkit for creating functionalized aromatic molecules.
- The reaction's compatibility with diverse conditions makes it suitable for broad applications in organic synthesis.
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Alkynes can be prepared by dehydrohalogenation of vicinal or geminal dihalides in the presence of a strong base like sodium amide in liquid ammonia. The reaction proceeds with the loss of two equivalents of hydrogen halide (HX) via two successive E2 elimination reactions.
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One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.
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