{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T01:43:05Z","timestamp":1760233385377,"version":"build-2065373602"},"reference-count":45,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,1,12]],"date-time":"2021-01-12T00:00:00Z","timestamp":1610409600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003329","name":"Ministerio de Econom\u00eda y Competitividad","doi-asserted-by":"publisher","award":["CTQ2016- 76908-C2-1-P, CTQ2016-76908-C2-2-P"],"award-info":[{"award-number":["CTQ2016- 76908-C2-1-P, CTQ2016-76908-C2-2-P"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100016970","name":"Consejer\u00eda de Econom\u00eda, Conocimiento, Empresas y Universidad, Junta de Andaluc\u00eda","doi-asserted-by":"publisher","award":["P18-FR-3531"],"award-info":[{"award-number":["P18-FR-3531"]}],"id":[{"id":"10.13039\/100016970","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Room temperature ionic liquids (RTILs) have been widely used as (co)solvents in several catalytic processes modifying, in most of the cases, the catalyst activity and\/or the selectivity for the studied reactions. However, there are just a few examples of their use in hydrogen bonding organocatalysis. In this paper, we show the positive effect of a set of imidazole-based ionic liquids ([bmim]BF4 and [hmim]PF6) in the enantioselective addition of formaldehyde tert-butylhydrazone to prochiral \u03b1-keto esters catalyzed by a sugar-based chiral thiourea. Reactions performed in the presence of low percentages of RTILs led to an increase of the catalyst activity, thereby making possible to work at lower temperatures. Thus, the chiral tert-butyl azomethyl tertiary alcohols could be obtained with moderate to good conversions and higher enantioselectivities for most of the studied substrates when using up to 30 vol% of [hmim]PF6 as a cosolvent in processes performed in toluene.<\/jats:p>","DOI":"10.3390\/molecules26020355","type":"journal-article","created":{"date-parts":[[2021,1,12]],"date-time":"2021-01-12T20:11:31Z","timestamp":1610482291000},"page":"355","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Room Temperature Ionic Liquids in Asymmetric Hetero-Ene Type Reactions: Improving Organocatalyst Performance at Lower Temperatures"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9153-1274","authenticated-orcid":false,"given":"Fabricio R.","family":"Bisogno","sequence":"first","affiliation":[{"name":"Facultad de Ciencias Qu\u00edmicas, Instituto de Investigaciones en F\u00edsico-Qu\u00edmica de C\u00f3rdoba, Universidad Nacional de C\u00f3rdoba, (INFIQC, CONICET-UNC), Haya de la Torre y Medina Allende, Ciudad Universitaria, C\u00f3rdoba 5000, Argentina"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rosario","family":"Fern\u00e1ndez","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica Org\u00e1nica, Universidad de Sevilla, c\/Profesor Garc\u00eda Gonz\u00e1lez 1, 41012 Sevilla, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1772-2723","authenticated-orcid":false,"given":"Jose Mar\u00eda","family":"Lassaletta","sequence":"additional","affiliation":[{"name":"Instituto de Investigaciones Qu\u00edmicas (CSIC-US) and Centro de Innovaci\u00f3n en Qu\u00edmica Avanzada (ORFEO-CINQA), Avda. Am\u00e9rico Vespucio 49, 41092 Sevilla, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0863-680X","authenticated-orcid":false,"given":"Gonzalo de","family":"de Gonzalo","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica Org\u00e1nica, Universidad de Sevilla, c\/Profesor Garc\u00eda Gonz\u00e1lez 1, 41012 Sevilla, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"112028","DOI":"10.1016\/j.molliq.2019.112038","article-title":"Ionic liquids synthesis and applications: An overview","volume":"297","author":"Singh","year":"2020","journal-title":"J. Mol. 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