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Synlett 2020; 31(20): 2027-2034
DOI: 10.1055/s-0040-1707261
letter

Pd-Catalyzed Functionalization of Aryl Amines on a Soluble Polymer Support

A. Sofia Santos
,
M. Manuel B. Marques  ∗
LAQV@REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal   Email: msbm@fct.unl.pt
› Author AffiliationsThis work was supported by the Associate Laboratory for Green Chemistry – LAQV which is financed by national funds from Fundação para a Ciência e a Tecnologia (FCT, UID/QUI/50006/2019) and the Ministry of Science, Technology and Higher Education (MCTES) and co-financed by the European Regional Development Fund (ERDF) under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007265). The National NMR Facility is supported by the Fundação para a Ciência e a Tecnologia (FCT, ROTEIRO/0031/2013 and PINFRA/22161/2016), co-financed by FEDER through COMPETE 2020, POCI, and PORL and FCT through PIDDAC). We thank to the Fundação para a Ciência e a Tecnologia (FCT) for fellowship (PD/BD/142876/2018).
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Abstract

Herein we report the use of a soluble polymer support PEG-2000 on Pd-catalyzed reactions to improve the functionalization of aromatic amines and the synthesis of N-heterocycles. Compatibility of metal-catalyzed reactions for assembling privileged structures such as functionalized anilines were studied. PEG-supported anilines were found to be suitable substrates for Pd-catalyzed N-arylation, Sonogashira and Heck reactions. PEGylated substrates were prepared in yields up to 94%. This work consists on a proof of concept on the use of PEGylated anilines on Pd-catalyzed cross-coupling reactions. Indole core was attained in 82% and 62% yields, via two different routes.

Key words

aryl amine - metal-catalyzed - PEG - functionalization - anilines

Supporting Information

    Supporting information for this article is available online at https://doi.org/10.1055/s-0040-1707261.
  • Supporting Information


Publication History

Received: 21 May 2020

Accepted after revision: 28 July 2020

Article published online:
03 September 2020

© 2020. Thieme. All rights reserved

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