{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,26]],"date-time":"2026-10-26T04:28:13Z","timestamp":1792988893659,"version":"4.5.0"},"reference-count":50,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2022,6,27]],"date-time":"2022-06-27T00:00:00Z","timestamp":1656288000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Oklahoma State University Foundation","award":["BIR-9512269"],"award-info":[{"award-number":["BIR-9512269"]}]},{"name":"College of Arts and Sciences at Oklahoma State University","award":["BIR-9512269"],"award-info":[{"award-number":["BIR-9512269"]}]},{"name":"OSU College of Arts and Sciences","award":["BIR-9512269"],"award-info":[{"award-number":["BIR-9512269"]}]},{"name":"NSF","award":["BIR-9512269"],"award-info":[{"award-number":["BIR-9512269"]}]},{"name":"Oklahoma State Regents for Higher Education","award":["BIR-9512269"],"award-info":[{"award-number":["BIR-9512269"]}]},{"name":"W. M. Keck Foundation","award":["BIR-9512269"],"award-info":[{"award-number":["BIR-9512269"]}]},{"name":"Conoco, Inc.","award":["BIR-9512269"],"award-info":[{"award-number":["BIR-9512269"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The Friedl\u00e4nder synthesis offers efficient access to substituted quinolines from 2-aminobenzaldehydes and activated ketones in the presence of a base. The disadvantage of this procedure lies in the fact that relatively few 2-aminobenzaldehyde derivatives are readily available. To overcome this problem, we report a modification of this process involving the in situ reduction of 2-nitrobenzaldehydes with Fe\/AcOH in the presence of active methylene compounds (AMCs) to produce substituted quinolines in high yields. The conditions are mild enough to tolerate a wide range of functionality in both reacting partners and promote reactions not only with phenyl and benzyl ketones, but also with \u03b2-keto-esters, \u03b2-keto-nitriles, \u03b2-keto-sulfones and \u03b2-diketones. The reaction of 2-nitroaromatic ketones with unsymmetrical AMCs is less reliable, giving a competitive formation of substituted quinolin-2(1H)-ones from the cyclization of the Z Knoevenagel intermediate which appears to be favored when certain large groups are adjacent to the AMC ketone carbonyl.<\/jats:p>","DOI":"10.3390\/molecules27134123","type":"journal-article","created":{"date-parts":[[2022,6,28]],"date-time":"2022-06-28T00:07:02Z","timestamp":1656374822000},"page":"4123","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Domino Nitro Reduction-Friedl\u00e4nder Heterocyclization for the Preparation of Quinolines"],"prefix":"10.3390","volume":"27","author":[{"given":"Kwabena","family":"Fobi","sequence":"first","affiliation":[{"name":"Department of Chemistry, Oklahoma State University, Stillwater, OK 74078-3071, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard A.","family":"Bunce","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Oklahoma State University, Stillwater, OK 74078-3071, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,27]]},"reference":[{"key":"ref_1","unstructured":"Katritzky, A.R., Ramsden, C.A., Joule, J.A., and Zhdankin, V.V. 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