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Chiral Induction in Intramolecular Rhodium-Catalyzed [2+2+2] Cycloadditions of Optically Active Allene-ene/yne-allene Substrates

Allene-yne-allene and allene-ene-allene N-tosyl-linked substrates with two chiral centres in the α-position of the allene moiety were satisfactorily prepared starting both from racemic and chiral propargylic alcohols. The Wilkinson’s complex-catalyzed [2+2+2] cycloaddition reaction of these substrates was evaluated. In the case of enantiomerically pure bisallenes, high stereoselectivity was observed, giving a diastereomerically pure cycloadduct. The chirality of starting bisallene substrates can be completely transferred to the cycloadducts, representing an atom-economical and enantiospecific process for the construction of fused polycycles. However, when reacting an oxygen-linked allene-ene-allene substrate, the stereoselectivity decreased and two diastereoisomers were formed. A detailed characterization study of the resulting cycloadducts allowed us to identify the enantioisomer generated in the cycloaddition

Financial support from the Spanish Ministry of Education and Science (MINECO) (Projects No.: CTQ2014–54306-P, CTQ2015-64436-P and SAF2014-52223-C2-1-R) and the DIUE of the Generalitat de Catalunya (Project No.: 2014SGR931 and predoctoral grant to M.F.) are acknowledged. Thanks are due to UdG for a predoctoral grant to E.H.

© Advanced Synthesis and Catalysis, 2016, vol. 359, núm. 3, p. 506-512

Wiley

Director: Ministerio de Economía y Competitividad (Espanya)
Autor: Haraburda, Ewelina
Fernández Wang, Martí
Gifreu, Anna
Garcia, Jordi
Parella Coll, Teodor
Pla i Quintana, Anna
Roglans i Ribas, Anna
Data: 2 febrer 2017
Resum: Allene-yne-allene and allene-ene-allene N-tosyl-linked substrates with two chiral centres in the α-position of the allene moiety were satisfactorily prepared starting both from racemic and chiral propargylic alcohols. The Wilkinson’s complex-catalyzed [2+2+2] cycloaddition reaction of these substrates was evaluated. In the case of enantiomerically pure bisallenes, high stereoselectivity was observed, giving a diastereomerically pure cycloadduct. The chirality of starting bisallene substrates can be completely transferred to the cycloadducts, representing an atom-economical and enantiospecific process for the construction of fused polycycles. However, when reacting an oxygen-linked allene-ene-allene substrate, the stereoselectivity decreased and two diastereoisomers were formed. A detailed characterization study of the resulting cycloadducts allowed us to identify the enantioisomer generated in the cycloaddition
Financial support from the Spanish Ministry of Education and Science (MINECO) (Projects No.: CTQ2014–54306-P, CTQ2015-64436-P and SAF2014-52223-C2-1-R) and the DIUE of the Generalitat de Catalunya (Project No.: 2014SGR931 and predoctoral grant to M.F.) are acknowledged. Thanks are due to UdG for a predoctoral grant to E.H.
Format: application/pdf
Cita: 026074
ISSN: 1615-4150 (versió paper)
1615-4169 (versió electrònica)
Accés al document: http://hdl.handle.net/10256/13482
Llenguatge: eng
Editor: Wiley
Col·lecció: MINECO/PE 2015-2017/CTQ2014-54306-P
Reproducció digital del document publicat a: http://dx.doi.org/10.1002/adsc.201600613
Articles publicats (D-Q)
És part de: © Advanced Synthesis and Catalysis, 2016, vol. 359, núm. 3, p. 506-512
Drets: Tots els drets reservats
Matèria: Ciclització (Química)
Ring formation (Chemistry)
Al·lens
Allenes
Rodi
Rhodium
Títol: Chiral Induction in Intramolecular Rhodium-Catalyzed [2+2+2] Cycloadditions of Optically Active Allene-ene/yne-allene Substrates
Tipus: info:eu-repo/semantics/article
Repositori: DUGiDocs

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