{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T18:06:28Z","timestamp":1780596388083,"version":"3.54.1"},"reference-count":37,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,2,22]],"date-time":"2022-02-22T00:00:00Z","timestamp":1645488000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100007195","name":"University of Naples Federico II","doi-asserted-by":"publisher","award":["HORIZON 2020-MSCA RISE 2018 GreenX4Drug project 823939"],"award-info":[{"award-number":["HORIZON 2020-MSCA RISE 2018 GreenX4Drug project 823939"]}],"id":[{"id":"10.13039\/100007195","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>Indole moiety is well-known as a superlative framework in many natural products and synthetic pharmaceuticals. Herein, we report an efficient procedure to synthesize a series of functionalized 2-methyl-1H-indole-3-carboxylate derivatives from commercially available anilines properly functionalized by different electron-withdrawing and -donating groups through a palladium-catalyzed intramolecular oxidative coupling. The conversion of a variety of enamines into the relevant indole was optimized by exposing the neat mixture of reactants to microwave irradiation, obtaining the desired products in excellent yields and high regioselectivity. The synthesized compounds were confirmed by 1H and 13C spectroscopic means as well as by high-resolution mass spectrometry.<\/jats:p>","DOI":"10.3390\/sym14030435","type":"journal-article","created":{"date-parts":[[2022,2,22]],"date-time":"2022-02-22T22:35:00Z","timestamp":1645569300000},"page":"435","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Microwave-Assisted Synthesis of 2-Methyl-1H-indole-3-carboxylate Derivatives via Pd-Catalyzed Heterocyclization"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2163-5163","authenticated-orcid":false,"given":"Rosa","family":"Bellavita","sequence":"first","affiliation":[{"name":"Department of Pharmacy, University of Naples \u201cFederico II\u201d, Via D. Montesano 49, 80131 Naples, Italy"},{"name":"KelAda Pharmachem Ltd. A1.01, Science Centre South, Belfield, D04 Dublin, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5037-712X","authenticated-orcid":false,"given":"Marcello","family":"Casertano","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, University of Naples \u201cFederico II\u201d, Via D. Montesano 49, 80131 Naples, Italy"},{"name":"KelAda Pharmachem Ltd. A1.01, Science Centre South, Belfield, D04 Dublin, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicola","family":"Grasso","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, University of Naples \u201cFederico II\u201d, Via D. Montesano 49, 80131 Naples, Italy"},{"name":"KelAda Pharmachem Ltd. A1.01, Science Centre South, Belfield, D04 Dublin, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Malachi","family":"Gillick-Healy","sequence":"additional","affiliation":[{"name":"KelAda Pharmachem Ltd. A1.01, Science Centre South, Belfield, D04 Dublin, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brian G.","family":"Kelly","sequence":"additional","affiliation":[{"name":"KelAda Pharmachem Ltd. A1.01, Science Centre South, Belfield, D04 Dublin, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mauro F. A.","family":"Adamo","sequence":"additional","affiliation":[{"name":"KelAda Pharmachem Ltd. A1.01, Science Centre South, Belfield, D04 Dublin, Ireland"},{"name":"Centre for Synthesis and Chemical Biology, Department of Chemistry, The Royal College of Surgeons in Ireland, 123 St. Stephen\u2032s Green, D02 YN77 Dublin, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4515-3014","authenticated-orcid":false,"given":"Marialuisa","family":"Menna","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, University of Naples \u201cFederico II\u201d, Via D. Montesano 49, 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9607-229X","authenticated-orcid":false,"given":"Francesco","family":"Merlino","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, University of Naples \u201cFederico II\u201d, Via D. Montesano 49, 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paolo","family":"Grieco","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, University of Naples \u201cFederico II\u201d, Via D. Montesano 49, 80131 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6620","DOI":"10.3390\/molecules18066620","article-title":"Biomedical Importance of Indoles","volume":"18","author":"Kaushik","year":"2013","journal-title":"Molecules"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"159","DOI":"10.1016\/j.ejmech.2017.04.003","article-title":"Indoles as therapeutics of interest in medicinal chemistry: Bird\u2019s eye view","volume":"134","author":"Chadha","year":"2017","journal-title":"Eur. J. Med. Chem."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"61","DOI":"10.1080\/02791072.1979.10472093","article-title":"Psilocin, Bufotenine and Serotonin: Historical and Biosynthetic Observations","volume":"11","author":"Chilton","year":"1979","journal-title":"J. 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