Aryl ether synthesis by etherification (arylation)
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Aryl ether synthesis by etherification (alkylation)
To conclude, transition-metal-free methodology to access sterically hindered alkyl aryl ethers by arylation of tertiary alcohols with -substituted diaryliodonium salts has been developed. The substrate scope includes cyclic, acyclic, propargylic, and allylic alcohols. The methodology has been extended to arylation of fluorinated primary and secondary alcohols and to arylations with electron-deficient -substituted diaryliodonium salts. The straightforward derivatization of the pro-drug mestranol illustrates the utility of the presented methodology. A detailed mechanistic study of -arylations with diaryliodonium salts is currently ongoing in our laboratory to understand the limitations in reactions with -unsubstituted electron-rich diaryliodonium salts.
Williamson ether synthesis - Wikipedia
In summary, a practical and efficient synthesis of new substituted aryl vinyl ethers 3 and diethyl 1-[(alkyl)(cyano)methyl]vinylphosphonates 4 has been developed. The application of diethyl (E)-1-(bromomethyl)-2-cyanovinylphosphonate 2 in other processes will be communicated in due course.
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1.6 Williamson ether synthesis by Gabbar Singh Tutorials ..
The synthesis of ethers and functionalization of alcohols are broad research areas due to the prevalent occurrence of these compound classes as both starting materials and products in Nature and pharmaceuticals. However, traditional methods for synthesis of alkyl aryl ethers are all associated with difficulties, and the arylation of tertiary alcohols with electron-rich or sterically hindered arenes to obtain highly sterically hindered ethers is severely limited (a). Among the methods based on arylation of alcohols, SNAr reactions can be used. The method tolerates sterically congested alcohols as well as -substituted arenes, but the scope is limited to arenes activated by electron-withdrawing groups. Another approach is via aryne-type intermediates, which generally suffer from regioselectivity issues and the lack of bis- substituent patterns. While some transition-metal-catalyzed methodologies are compatible with tertiary alcohols, the combination of such substrates with -substituted aryl groups remains difficult, and examples with bis--substituted aryl groups are lacking. Furthermore, these methods usually require high temperatures and have problems associated with remaining traces of transition metals.