{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T15:09:41Z","timestamp":1789139381240,"version":"build-2803163510"},"reference-count":32,"publisher":"American Chemical Society (ACS)","issue":"36","license":[{"start":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T00:00:00Z","timestamp":1787788800000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-029"},{"start":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T00:00:00Z","timestamp":1787788800000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-037"},{"start":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T00:00:00Z","timestamp":1787788800000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-045"}],"funder":[{"DOI":"10.13039\/501100003819","name":"Natural Science Foundation of Hubei Province","doi-asserted-by":"publisher","award":["2025AFB229"],"award-info":[{"award-number":["2025AFB229"]}],"id":[{"id":"10.13039\/501100003819","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003819","name":"Natural Science Foundation of Hubei Province","doi-asserted-by":"publisher","award":["2026AFC0028"],"award-info":[{"award-number":["2026AFC0028"]}],"id":[{"id":"10.13039\/501100003819","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Hubei Key Laboratory of Pollutant Analysis and Reuse Technology"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,9,11]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>A regioselective palladium-catalyzed C3\u2013H arylation of 1,2,4-triazolo[4,3-b]pyridazines with readily accessible aryl thianthrenium salts has been developed. This method provides direct access to a diverse array of C3-arylated triazolopyridazines in moderate to excellent yields under mild and operationally simple conditions. A broad substrate scope and excellent functional-group tolerance were observed for both coupling partners. The synthetic utility of the protocol was further demonstrated by gram-scale synthesis. Mechanistic studies, including competition and radical-trapping experiments, support a Pd(0)\/Pd(II) catalytic pathway and rule out the involvement of radical intermediates. This work offers an efficient approach to the direct C3 functionalization of triazolopyridazines and highlights the potential of aryl thianthrenium salts as valuable arylation reagents in heterocycle synthesis.<\/jats:p>","DOI":"10.1021\/acs.orglett.6c03033","type":"journal-article","created":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T16:04:57Z","timestamp":1788278697000},"page":"11231-11236","source":"Crossref","is-referenced-by-count":0,"title":["Regioselective\nPalladium-Catalyzed Direct C3\u2013H\nArylation of Triazolopyridazines with Aryl Thianthrenium Salts"],"prefix":"10.1021","volume":"28","author":[{"given":"Na","family":"Wang","sequence":"first","affiliation":[{"name":"Hubei Normal University , , ,","place":["Huangshi, P. R. China, 435002"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peifeng","family":"Li","sequence":"additional","affiliation":[{"name":"Hubei Normal University , , ,","place":["Huangshi, P. R. China, 435002"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Liwen","family":"Xia","sequence":"additional","affiliation":[{"name":"Hubei Normal University , , ,","place":["Huangshi, P. R. China, 435002"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dongcheng","family":"Wang","sequence":"additional","affiliation":[{"name":"Hubei Normal University , , ,","place":["Huangshi, P. R. China, 435002"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5425-7421","authenticated-orcid":true,"given":"Jinhua","family":"Yang","sequence":"additional","affiliation":[{"name":"Hubei Normal University , , ,","place":["Huangshi, P. R. China, 435002"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-9757-0204","authenticated-orcid":true,"given":"Chunyu","family":"Han","sequence":"additional","affiliation":[{"name":"Hubei Normal University , , ,","place":["Huangshi, P. R. 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