{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,24]],"date-time":"2026-07-24T13:29:04Z","timestamp":1784899744209,"version":"3.55.0"},"reference-count":103,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2025,8,27]],"date-time":"2025-08-27T00:00:00Z","timestamp":1756252800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100017242","name":"Key Technology Research Fund of the China National Institutes for Food and Drug Control","doi-asserted-by":"publisher","award":["GJJS-2022-5-2"],"award-info":[{"award-number":["GJJS-2022-5-2"]}],"id":[{"id":"10.13039\/100017242","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>This paper reviews a substantial amount of research related to the Eschweiler\u2013Clarke methylation reaction, summarizing its mechanism, development, and applications, to present the chemical essence and history of this reaction and its importance and application in modern synthetic chemistry. In particular, this review focuses on advances regarding the Eschweiler\u2013Clarke methylation reaction since 2000. This work will provide researchers with a comprehensive and in-depth perspective of the Eschweiler\u2013Clarke reaction, as well as guidance and inspiration for future research and application.<\/jats:p>","DOI":"10.3390\/molecules30173504","type":"journal-article","created":{"date-parts":[[2025,8,27]],"date-time":"2025-08-27T08:19:32Z","timestamp":1756282772000},"page":"3504","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Review of Modern Eschweiler\u2013Clarke Methylation Reaction"],"prefix":"10.3390","volume":"30","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3411-4335","authenticated-orcid":false,"given":"Xiaoli","family":"Zhou","sequence":"first","affiliation":[{"name":"National Institutes for Food and Drug Control, Beijing 102629, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xue","family":"Ni","sequence":"additional","affiliation":[{"name":"National Institutes for Food and Drug Control, Beijing 102629, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xianfu","family":"Wu","sequence":"additional","affiliation":[{"name":"National Institutes for Food and Drug Control, Beijing 102629, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-3455-0216","authenticated-orcid":false,"given":"Lihui","family":"Yin","sequence":"additional","affiliation":[{"name":"National Institutes for Food and Drug Control, Beijing 102629, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5215","DOI":"10.1021\/cr200060g","article-title":"The methylation effect in medicinal chemistry","volume":"111","author":"Barreiro","year":"2011","journal-title":"Chem. 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