{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T05:09:04Z","timestamp":1789016944072,"version":"build-2803163510"},"reference-count":36,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T00:00:00Z","timestamp":1788480000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["22178205"],"award-info":[{"award-number":["22178205"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["22178205"],"award-info":[{"award-number":["22178205"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>An efficient, catalyst-free, and room-temperature protocol has been developed for the ring-opening reactions of ring cyclic ethers with indoles in Hexafluoroisopropanol (HFIP). Under these mild conditions, a diverse range of indoles smoothly reacted with oxirane within 6 h, affording the corresponding C3-alkylated indoles in good-to-excellent yields. Notably, this method also shows promising reactivity toward four-membered oxetanes. Furthermore, stereospecific investigations employing enantiopure (R)-styrene oxide afforded the corresponding products with high enantiomeric excess, suggesting an SN2 pathway with inversion of configuration. The unique hydrogen-bonding ability and acidity of HFIP are crucial for driving this facile transformation. This protocol offers a green, atom-economical, and sustainable approach for constructing structurally diverse indole derivatives, showcasing high practical utility for organic synthesis.<\/jats:p>","DOI":"10.3390\/molecules31173108","type":"journal-article","created":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T16:07:32Z","timestamp":1788538052000},"page":"3108","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Hexafluoroisopropanol Mediated Ring-Opening Reactions of Epoxides with Indoles Under Catalyst-Free Conditions"],"prefix":"10.3390","volume":"31","author":[{"given":"Yangmin","family":"Ma","sequence":"first","affiliation":[{"name":"Key Laboratory of Chemical Additives, China National Light Industry, College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi\u2019an 710021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ding","family":"Ma","sequence":"additional","affiliation":[{"name":"Key Laboratory of Chemical Additives, China National Light Industry, College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi\u2019an 710021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhichao","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Chemical Additives, China National Light Industry, College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi\u2019an 710021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Murong","family":"Zhan","sequence":"additional","affiliation":[{"name":"Key Laboratory of Chemical Additives, China National Light Industry, College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi\u2019an 710021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qian","family":"Jiao","sequence":"additional","affiliation":[{"name":"Key Laboratory of Chemical Additives, China National Light Industry, College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi\u2019an 710021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sen","family":"Yang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Chemical Additives, China National Light Industry, College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi\u2019an 710021, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e202500121","DOI":"10.1002\/tcr.202500121","article-title":"Chemistry, Applications, and Synthesis Methods of Indole Derivatives: A Comprehensive Review","volume":"25","year":"2025","journal-title":"Chem. 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