{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T13:27:16Z","timestamp":1791898036842,"version":"4.3.4"},"reference-count":58,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,1,26]],"date-time":"2021-01-26T00:00:00Z","timestamp":1611619200000},"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>1-Methyl-3,5-dinitro-2-pyridone serves as an excellent substrate for nucleophilic-type ring transformation because of the electron deficiency and presence of a good leaving group. In this review, we focus on the three-component ring transformation (TCRT) of dinitropyridone involving a ketone and a nitrogen source. When dinitropyridone is allowed to react with a ketone in the presence of ammonia, TCRT proceeds to afford nitropyridines that are not easily produced by alternative procedures. Ammonium acetate can be used as a nitrogen source instead of ammonia to undergo the TCRT, leading to nitroanilines in addition to nitropyridines. In these reactions, dinitropyridone serves as a safe synthetic equivalent of unstable nitromalonaldehyde.<\/jats:p>","DOI":"10.3390\/molecules26030639","type":"journal-article","created":{"date-parts":[[2021,1,26]],"date-time":"2021-01-26T23:01:28Z","timestamp":1611702088000},"page":"639","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Synthesis of Nitroaromatic Compounds via Three-Component Ring Transformations"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5357-9023","authenticated-orcid":false,"given":"Song Thi","family":"Le","sequence":"first","affiliation":[{"name":"School of Environmental Science and Engineering, Kochi University of Technology, Tosayamada, Kami, Kochi 782-8502, Japan"},{"name":"Center for Equipment and Labour Safety, Vietnam Institute for Building Materials (VIBM), Ministry of Construction, 235 Nguyen Trai, Thanh Xuan, Hanoi 100000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1808-7373","authenticated-orcid":false,"given":"Haruyasu","family":"Asahara","sequence":"additional","affiliation":[{"name":"School of Environmental Science and Engineering, Kochi University of Technology, Tosayamada, Kami, Kochi 782-8502, Japan"},{"name":"Research Center for Molecular Design, Kochi University of Technology, Tosayamada, Kami, Kochi 782-8502, Japan"},{"name":"Graduate School of Pharmaceutical Sciences, Osaka University, Yamadaoka 1-6, Suita, Osaka 565-0871, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6052-8697","authenticated-orcid":false,"given":"Nagatoshi","family":"Nishiwaki","sequence":"additional","affiliation":[{"name":"School of Environmental Science and Engineering, Kochi University of Technology, Tosayamada, Kami, Kochi 782-8502, Japan"},{"name":"Research Center for Molecular Design, Kochi University of Technology, Tosayamada, Kami, Kochi 782-8502, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6055","DOI":"10.1021\/acs.orglett.8b02431","article-title":"Metal-Free Formal Inverse-Electron-Demand Diels\u2013Alder Reaction of 1,2-Diazines with Ynamides","volume":"20","author":"Xue","year":"2018","journal-title":"Org. 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