{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T16:22:01Z","timestamp":1776874921136,"version":"3.51.2"},"reference-count":41,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2019,12,2]],"date-time":"2019-12-02T00:00:00Z","timestamp":1575244800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The Deutsche Forschungsgemeinschaft (DFG), Bonn","award":["Grant # Schr 597\/34-1"],"award-info":[{"award-number":["Grant # Schr 597\/34-1"]}]},{"DOI":"10.13039\/501100004281","name":"Narodowe Centrum Nauki","doi-asserted-by":"publisher","award":["Grant # 2016\/23\/G\/ST5\/04115\/l"],"award-info":[{"award-number":["Grant # 2016\/23\/G\/ST5\/04115\/l"]}],"id":[{"id":"10.13039\/501100004281","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>\u2018Desymmetrization\u2019 of trans-1,2-diaminocyclohexane by treatment with \u03b1,\u03c9-dihalogenated alkylation reagents leads to mono-NH2 derivatives (\u2018primary-tertiary diamines\u2019). Upon reaction with formaldehyde, these products formed monomeric formaldimines. Subsequently, reactions of the formaldimines with \u03b1-hydroxyiminoketones led to the corresponding 2-unsubstituted imidazole N-oxide derivatives, which were used here as new substrates for the in situ generation of chiral imidazol-2-ylidenes. Upon O-selective benzylation, new chiral imidazolium salts were obtained, which were deprotonated by treatment with triethylamine in the presence of elemental sulfur. Under these conditions, the intermediate imidazol-2-ylidenes were trapped by elemental sulfur, yielding the corresponding chiral non-enolizable imidazole-2-thiones in good yields. Analogous reaction sequences, starting with imidazole N-oxides derived from enantiopure primary amines, amino alcohols, and amino acids, leading to the corresponding 3-alkoxyimidazole-2-thiones were also studied.<\/jats:p>","DOI":"10.3390\/molecules24234398","type":"journal-article","created":{"date-parts":[[2019,12,2]],"date-time":"2019-12-02T10:50:45Z","timestamp":1575283845000},"page":"4398","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["2-Unsubstituted Imidazole N-Oxides as Novel Precursors of Chiral 3-Alkoxyimidazol-2-ylidenes Derived from trans-1,2-Diaminocyclohexane and Other Chiral Amino Compounds"],"prefix":"10.3390","volume":"24","author":[{"given":"Grzegorz","family":"Mlosto\u0144","sequence":"first","affiliation":[{"name":"Department of Organic and Applied Chemistry, University of \u0141\u00f3d\u017a, Tamka 12, PL-91-403 \u0141\u00f3d\u017a, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ma\u0142gorzata","family":"Celeda","sequence":"additional","affiliation":[{"name":"Department of Organic and Applied Chemistry, University of \u0141\u00f3d\u017a, Tamka 12, PL-91-403 \u0141\u00f3d\u017a, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8789-9690","authenticated-orcid":false,"given":"Marcin","family":"Jasi\u0144ski","sequence":"additional","affiliation":[{"name":"Department of Organic and Applied Chemistry, University of \u0141\u00f3d\u017a, Tamka 12, PL-91-403 \u0141\u00f3d\u017a, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Katarzyna","family":"Urbaniak","sequence":"additional","affiliation":[{"name":"Department of Organic and Applied Chemistry, University of \u0141\u00f3d\u017a, Tamka 12, PL-91-403 \u0141\u00f3d\u017a, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7139-8568","authenticated-orcid":false,"given":"Przemys\u0142aw J.","family":"Boraty\u0144ski","sequence":"additional","affiliation":[{"name":"Department of Organic Chemistry, Wroc\u0142aw University of Technology, Wyspia\u0144skiego 27, PL-50-370 Wroc\u0142aw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3608-5515","authenticated-orcid":false,"given":"Peter R.","family":"Schreiner","sequence":"additional","affiliation":[{"name":"Justus Liebig University, Institute of Organic Chemistry, Heinrich-Buff-Ring 17, D-35392 Giessen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5145-4251","authenticated-orcid":false,"given":"Heinz","family":"Heimgartner","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,12,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"361","DOI":"10.1021\/ja00001a054","article-title":"A stable crystalline carbene","volume":"113","author":"Arduengo","year":"1991","journal-title":"J. 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