2026-05-27T03:59:06Zhttps://riubu.ubu.es/oai/request

oai:riubu.ubu.es:10259/38952022-12-19T09:36:20Zcom_10259_3593com_10259_5086com_10259_2604col_10259_3594

2016-02-09T03:45:06Z urn:hdl:10259/3895 Gold(I)-Catalyzed Cycloisomerizations and Alkoxycyclizations of ortho-(Alkynyl)styrenes Sanjuán Cortázar, Ana María Rashid, Muhammad A. García García, Patricia Martínez Cuezva, Alberto Fernández Rodríguez, Manuel A. Rodríguez, Félix Sanz Díez, Roberto asymmetric catalysis cyclization cycloisomerization gold indenes Indenes and related polycyclic structures have been efficiently synthesized by gold(I)-catalyzed cycloisomerizations of appropriate ortho-(alkynyl)styrenes. Disubstitution at the terminal position of the olefin was demonstrated to be essential to obtain products originating from a formal 5-endo-dig cyclization. Interestingly, a complete switch in the selectivity of the cyclization of o-(alkynyl)-α-methylstyrenes from 6-endo to 5-endo was observed by adding an alcohol to the reaction media. This allowed the synthesis of interesting indenes bearing an all-carbon quaternary center at C1. Moreover, dihydrobenzo[a]fluorenes can be obtained from substrates bearing a secondary alkyl group at the β-position of the styrene moiety by a tandem cycloisomerization/1,2-hydride migration process. In addition, diverse polycyclic compounds were obtained by an intramolecular gold-catalyzed alkoxycyclization of o-(alkynyl)styrenes bearing a nucleophile in their structure. Finally, the use of a chiral gold complex allowed access to elusive chiral 1H-indenes in good enantioselectivities 2015-12-10T12:48:00Z 2016-02-09T03:45:06Z 2015-02 info:eu-repo/semantics/article 0947-6539 http://hdl.handle.net/10259/3895 10.1002/chem.201405789 eng Chemistry-A european journal. 2015. V. 21, n. 7, p. 3042-3052 http://dx.doi.org/10.1002/chem.201405789 info:eu-repo/grantAgreement/MINECO/CTQ2010-15358 info:eu-repo/grantAgreement/MINECO/CTQ2013-48937-C2-1-P info:eu-repo/grantAgreement/MEC/SB2009-0186 info:eu-repo/grantAgreement/JCyL/BU237U13 info:eu-repo/semantics/openAccess Wiley-VCH Verlag