Ligand-Free Palladium-Catalyzed Oxyarylation of Dihydronaphthalenes and Chromenequinone with o-Iodophenols and 3-Iodolawsone in PEG-400: An Efficient Synthesis of 5-Carbapterocarpans and Pterocarpanquinones
Contribuinte(s) |
Universidad de Alicante. Departamento de Química Orgánica Síntesis Asimétrica (SINTAS) |
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Data(s) |
28/01/2016
28/01/2016
11/09/2015
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Resumo |
Dihydronaphthalenes were oxyarylated with o-iodophenols, in PEG-400 at 140 or 170 °C, leading regio- and stereoselectively to 5-carbapterocarpans. By using Pd(OAc)2 (5–10 mol%) as precatalyst and Ag2CO3 (1.1 equiv) as base (conditions A), products were obtained in good to excellent chemical yields, in 5–30 minutes, irrespective of the pattern of substitution the starting materials. Alternatively, when p-hydroxyacetophenone oxime derived palladacycle (1 mol%) was used as precatalyst, and dicyclohexylamine (2 equiv) was used as base (silver-free, conditions B), the corresponding adducts were obtained in moderate to good yields, in 0.5 to 4 hours. Finally, the oxyarylation of dihydronaphthalenes and chromenquinone with o-iodophenols and 3-iodolawsone in PEG-400 under conditions A led regio- and stereoselectively to the formation of carbapterocarpanquinones and pterocarpanquinones in moderate yield. Financial support from Brazilian agencies CAPES-DGU (Project 200/09), CNPq, FAPERJ and UFRJ are acknowledged. Spanish MICINN (Projects PHB2008-0037-PC, CTQ2007-62771/BQU, CTQ2010-20387, Consolider INGENIO 2010 CSD2007-00006), FEDER, Generalitat Valenciana (Project PROMETEO/2009/038), and the University of Alicante are acknowledged. |
Identificador |
Synthesis. 2015, 47(22): 3505-3512. doi:10.1055/s-0034-1378745 0039-7881 (Print) 1437-210X (Online) http://hdl.handle.net/10045/52711 10.1055/s-0034-1378745 |
Idioma(s) |
eng |
Publicador |
Georg Thieme Verlag |
Relação |
http://dx.doi.org/10.1055/s-0034-1378745 |
Direitos |
© Georg Thieme Verlag Stuttgart · New York info:eu-repo/semantics/openAccess |
Palavras-Chave | #Oxyarylation reaction #PEG #Carbapterocarpans #Pterocarpanquinones #Oxygen heterocycles #Química Orgánica |
Tipo |
info:eu-repo/semantics/article |