{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T13:26:02Z","timestamp":1783344362880,"version":"3.54.6"},"reference-count":41,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2014,1,17]],"date-time":"2014-01-17T00:00:00Z","timestamp":1389916800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>An efficient method for the synthesis of a variety of pyrimidine derivatives 3a\u2013t by reaction of barbituric acids 1a,b as Michael donor with nitroalkenes 2a\u2013k as Michael acceptor using an aqueous medium and diethylamine is described. This 1,4-addition strategy offers several advantages, such as using an economic and environmentally benign reaction media, high yields, versatility, and shorter reaction times. The synthesized compounds were identified by 1H-NMR, 13C-NMR, CHN, IR, and MS. The structure of compound 3a was further confirmed by single crystal X-ray structure determination.<\/jats:p>","DOI":"10.3390\/molecules19011150","type":"journal-article","created":{"date-parts":[[2014,1,17]],"date-time":"2014-01-17T12:48:09Z","timestamp":1389962889000},"page":"1150-1162","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["A Greener, Efficient Approach to Michael Addition of Barbituric Acid to Nitroalkene in Aqueous  Diethylamine Medium"],"prefix":"10.3390","volume":"19","author":[{"given":"Hany","family":"Al-Najjar","sequence":"first","affiliation":[{"name":"Department of Chemistry, College of Science, King Saud University, P. O. Box 2455,  Riyadh 11451, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7885-3201","authenticated-orcid":false,"given":"Assem","family":"Barakat","sequence":"additional","affiliation":[{"name":"Department of Chemistry, College of Science, King Saud University, P. O. Box 2455,  Riyadh 11451, Saudi Arabia"},{"name":"Department of Chemistry, Faculty of Science, Alexandria University, P.O. Box 426,  Ibrahimia- 21321 Alexandria, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdullah","family":"Al-Majid","sequence":"additional","affiliation":[{"name":"Department of Chemistry, College of Science, King Saud University, P. O. Box 2455,  Riyadh 11451, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9762-0323","authenticated-orcid":false,"given":"Yahia","family":"Mabkhot","sequence":"additional","affiliation":[{"name":"Department of Chemistry, College of Science, King Saud University, P. O. Box 2455,  Riyadh 11451, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Manuel","family":"Weber","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of California, Berkeley, CA 94720, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1011-0276","authenticated-orcid":false,"given":"Hazem","family":"Ghabbour","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University,  P. O. Box 2457, Riyadh 11451, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hoong-Kun","family":"Fun","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University,  P. O. Box 2457, Riyadh 11451, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2014,1,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8033","DOI":"10.1016\/S0040-4020(00)00618-9","article-title":"Enantioselective conjugate additions","volume":"56","author":"Sibi","year":"2000","journal-title":"Tetrahedron"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1877","DOI":"10.1002\/1099-0690(200206)2002:12<1877::AID-EJOC1877>3.0.CO;2-U","article-title":"Asymmetric Michael additions to nitroalkenes","volume":"2002","author":"Berner","year":"2002","journal-title":"Eur. J. 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