{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,9]],"date-time":"2026-10-09T13:53:02Z","timestamp":1791553982479,"version":"4.3.4"},"reference-count":37,"publisher":"American Chemical Society (ACS)","issue":"40","license":[{"start":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T00:00:00Z","timestamp":1790294400000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-029"},{"start":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T00:00:00Z","timestamp":1790294400000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-037"},{"start":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T00:00:00Z","timestamp":1790294400000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-045"}],"funder":[{"DOI":"10.13039\/501100004199","name":"Okinawa Institute of Science and Technology Graduate University","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100004199","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,10,9]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Enantioselective Mannich reactions of ketones, including functionalized ketones, with N-unprotected ketimines of isatin derivatives are reported. These reactions are catalyzed by amine-based catalysts and afford highly enantiomerically enriched 3-substituted 3-aminooxindole derivatives as single regioisomers under mild conditions. The use of N-unprotected imines minimizes the need for protection and deprotection steps. The reactions enabled the enantioselective construction of tetrasubstituted carbon centers and generated unprotected primary amine groups upon C\u2013C bond formation with the N-unprotected ketimines. The primary amine groups generated in the products did not interfere with the aminocatalysis. The reactions did not require either a decarboxylative strategy (i.e., the use of \u03b2-ketoacid derivatives as reactants) or preformed enol ether derivatives to obtain the Mannich reaction products with high regio- and enantioselectivities.<\/jats:p>","DOI":"10.1021\/acs.joc.6c01844","type":"journal-article","created":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T17:02:28Z","timestamp":1790355748000},"page":"13500-13506","source":"Crossref","is-referenced-by-count":0,"title":["Asymmetric Mannich\nReactions of Ketones with Isatin-Derived\n                    <i>N<\/i>\n                    -Unprotected\nKetimines Catalyzed by Amine Derivatives"],"prefix":"10.1021","volume":"91","author":[{"given":"Kamal","family":"Verma","sequence":"first","affiliation":[{"name":"Okinawa Institute of Science and Technology Graduate University , , 1919-1 Tancha, Onna , ,","place":["Okinawa, Japan, 904-0495"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rina","family":"Tokuyama","sequence":"additional","affiliation":[{"name":"Okinawa Institute of Science and Technology Graduate University , , 1919-1 Tancha, Onna , ,","place":["Okinawa, Japan, 904-0495"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6388-9343","authenticated-orcid":true,"given":"Fujie","family":"Tanaka","sequence":"additional","affiliation":[{"name":"Okinawa Institute of Science and Technology Graduate University , , 1919-1 Tancha, Onna , ,","place":["Okinawa, Japan, 904-0495"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,9,25]]},"reference":[{"key":"2026100909093515300_cit1a","doi-asserted-by":"publisher","first-page":"8708","DOI":"10.1021\/acs.orglett.0c03305","article-title":"A Bispidine-Based Chiral Amine Catalyst for Asymmetric Mannich Reaction\nof Ketones with Isatin Ketimines","volume":"22","author":"Li","year":"2020","journal-title":"Org. 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