α-Lithiobenzyloxy as a Directed Metalation Group in ortho-Lithiation Reactions

The α-lithiobenzyloxy group, easily generated from aryl benzyl ethers by selective α-lithiation with t-BuLi at low temperature, behaves as a directed metalation group (DMG) providing a direct access to o-lithiophenyl α-lithiobenzyl ethers. This ortho-directing effect is reinforced in substrates bear...

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Detalhes bibliográficos
Autores: Sedano Labrador, Carlos, Velasco, Rocío, Feberero, Claudia, Suarez Pantiga, Samuel, Sanz Díez, Roberto
Tipo de documento: artigo
Estado:Versión aceptada para publicación
Data de publicação:2020
País:España
Recursos:Universidad de Burgos (UBU)
Repositório:Repositorio Institucional de la Universidad de Burgos (RIUBU)
OAI Identifier:oai:riubu.ubu.es:10259/5534
Acesso em linha:http://hdl.handle.net/10259/5534
Access Level:Acceso aberto
Palavra-chave:Functionalization
Ethers
Rearrangement
Reaction products
Pharmaceuticals
Química orgánica
Chemistry, Organic
Descrição
Resumo:The α-lithiobenzyloxy group, easily generated from aryl benzyl ethers by selective α-lithiation with t-BuLi at low temperature, behaves as a directed metalation group (DMG) providing a direct access to o-lithiophenyl α-lithiobenzyl ethers. This ortho-directing effect is reinforced in substrates bearing an additional methoxy group at the meta position. The generated dianions can be reacted with a selection of electrophiles including carboxylic esters and dihalosilanes or germanes, which afford interesting benzofuran, sila(germa)dihydrobenzofuran, and silachroman derivatives from simple aryl benzyl ethers.