Catalytic regioselective isomerization of 2,2-disubstituted oxetanes to homoallylic alcohols

The selective isomerization of strained heterocyclic compounds is an important tool in organic synthesis. An unprecedented regioselective isomerization of 2,2-disubstituted oxetanes into homoallylic alcohols is described. The use of tris(pentafluorophenyl)borane (B(C6F5)3), a commercially available...

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Detalles Bibliográficos
Autores: Cabré, Albert|||0000-0003-4367-2635, Rafael, Sergi, Sciortino, Giuseppe|||0000-0001-9657-1788, Ujaque, Gregori|||0000-0001-5896-9998, Verdaguer, Xavier|||0000-0002-9229-969X, Lledós, Agustí|||0000-0001-7909-422X, Riera, Antoni|||0000-0001-7142-7675
Tipo de recurso: artículo
Fecha de publicación:2020
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:279264
Acceso en línea:https://ddd.uab.cat/record/279264
https://dx.doi.org/urn:doi:10.1002/anie.201915772
Access Level:acceso abierto
Palabra clave:Allylic compounds
Asymmetric catalysis
Boron
Hydrogenation
Isomerization
Descripción
Sumario:The selective isomerization of strained heterocyclic compounds is an important tool in organic synthesis. An unprecedented regioselective isomerization of 2,2-disubstituted oxetanes into homoallylic alcohols is described. The use of tris(pentafluorophenyl)borane (B(C6F5)3), a commercially available Lewis acid was key to obtaining good yields and selectivities since other Lewis acids afforded mixtures of isomers and substantial polymerization. The reaction took place under exceptionally mild reaction conditions and very low catalyst loading (0.5 mol %). DFT calculations disclose the mechanistic features of the isomerization and account for the high selectivity displayed by the B(C6F5)3 catalyst. The synthetic applicability of the new reaction is demonstrated by the preparation of γ-chiral alcohols using iridium-catalyzed asymmetric hydrogenation.