{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T10:59:09Z","timestamp":1791197949772,"version":"4.1.0"},"reference-count":34,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,10,4]],"date-time":"2026-10-04T00:00:00Z","timestamp":1791072000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>A triethanolamine (TEOA)-catalyzed, one-pot, three-component reaction of 4-hydroxycoumarin, aldehydes, and malononitrile was developed as a highly atom-economic domino protocol for the synthesis of biologically significant 4H-pyrano[3,2-c]coumarins. This cascade sequence proceeds through the successive formation of three new \u03c3 bonds (two C\u2014C and one C\u2014O). The protocol exhibited a broad substrate scope and proceeded rapidly and efficiently in methanol at ambient temperature or in water at 85 \u00b0C. 4H-Pyrano[3,2-c]coumarins were isolated in 51\u201395% yields using a simple workup without column chromatography. Sustained TEOA catalytic activity across seven consecutive cycles was demonstrated. Gram- and decagram-scale protocols were elaborated, and the plausible mechanistic pathway was proposed in this study.<\/jats:p>","DOI":"10.3390\/molecules31193541","type":"journal-article","created":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T10:02:27Z","timestamp":1791194547000},"page":"3541","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Triethanolamine-Catalyzed One-Pot Three-Component Domino Annulation Leading to 4H-Pyrano[3,2-c]coumarins: Catalyst Reusability and Decagram-Scale Synthesis"],"prefix":"10.3390","volume":"31","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5570-1427","authenticated-orcid":false,"given":"Essam M.","family":"Eliwa","sequence":"first","affiliation":[{"name":"Chemistry Department, Faculty of Science, Al-Azhar University, Nasr City 11884, Cairo, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2045-6887","authenticated-orcid":false,"given":"Atheer A.","family":"Mahmood","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biochemistry, College of Medicine, Al-Iraqia University, Baghdad 7366, Iraq"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Rania S.","family":"Ali","sequence":"additional","affiliation":[{"name":"Department of Basic Science, Faculty of Technology and Education, Capital University, Cairo 11281, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"}]},{"given":"Marwa ElS.","family":"Ahmed","sequence":"additional","affiliation":[{"name":"Chemistry Department, Faculty of Women for Art, Science and Education, Ain Shams University, Heliopolis 11757, Cairo, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"}]},{"given":"Abdullah A.","family":"Ahmed","sequence":"additional","affiliation":[{"name":"Chemistry Department, Faculty of Science, Al-Azhar University, Nasr City 11884, Cairo, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4832-5766","authenticated-orcid":false,"given":"Ewies F.","family":"Ewies","sequence":"additional","affiliation":[{"name":"Organometallic and Organometalloid Chemistry Department, National Research Centre, 33 ElBohouth St., (Former El Tahrir) Dokki, Giza 12622, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"visualization","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2608-9694","authenticated-orcid":false,"given":"Roman","family":"Dembinski","sequence":"additional","affiliation":[{"name":"Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 \u0141\u00f3d\u017a, Poland"},{"name":"Department of Chemistry, Oakland University, 146 Library Dr., Rochester, MI 48309-4479, USA"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,10,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Li, H.J., and Wang, L. 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