{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T10:13:32Z","timestamp":1788257612111,"version":"build-2803163510"},"reference-count":48,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,2,22]],"date-time":"2021-02-22T00:00:00Z","timestamp":1613952000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>CrCl3(thf)3 is a common starting material in the synthesis of organometallic and coordination compounds of Cr. Deposited as an irregular solid with no possibility of recrystallization, it is not a purity guaranteed chemical, causing problems in some cases. In this work, we disclose a well-defined form of the THF adduct of CrCl3 ([CrCl2(\u03bc-Cl)(thf)2]2), a crystalline solid, that enables structure determination by X-ray crystallography. The EA data and XRD pattern of the bulk agreed with the revealed structure. Moreover, its preparation procedure is facile: evacuation of CrCl3\u00b76H2O at 100 \u00b0C, treatment with 6 equivalents of Me3SiCl in a minimal amount of THF, and crystallization from CH2Cl2. The ethylene tetramerization catalyst [iPrN{P(C6H4-p-Si(nBu)3)2}2CrCl2]+[B(C6F5)4]\u2212 prepared using well-defined [CrCl2(\u03bc-Cl)(thf)2]2 as a starting material exhibited a reliably high activity (6600 kg\/g-Cr\/h; 1-octene selectivity at 40 \u00b0C, 75%), while that of the one prepared using the impure CrCl3(thf)3 was inconsistent and relatively low (~3000 kg\/g-Cr\/h). By using well-defined [CrCl2(\u03bc-Cl)(thf)2]2 as a Cr source, single crystals of [(CH3CN)4CrCl2]+[B(C6F5)4]\u2212 and [{Et(Cl)Al(N(iPr)2)2}Cr(\u03bc-Cl)]2 were obtained, allowing structure determination by X-ray crystallography, which had been unsuccessful when the previously known CrCl3(thf)3 was used as the Cr source.<\/jats:p>","DOI":"10.3390\/molecules26041167","type":"journal-article","created":{"date-parts":[[2021,2,22]],"date-time":"2021-02-22T20:42:51Z","timestamp":1614026571000},"page":"1167","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Replacement of the Common Chromium Source CrCl3(thf)3 with Well-Defined [CrCl2(\u03bc-Cl)(thf)2]2"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5114-7577","authenticated-orcid":false,"given":"Dong Geun","family":"Lee","sequence":"first","affiliation":[{"name":"Department of Molecular Science and Technology, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 16499, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jun Won","family":"Baek","sequence":"additional","affiliation":[{"name":"Department of Molecular Science and Technology, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 16499, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jung Hyun","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Molecular Science and Technology, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 16499, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hyun Ju","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Molecular Science and Technology, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 16499, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yeong Hyun","family":"Seo","sequence":"additional","affiliation":[{"name":"Department of Molecular Science and Technology, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 16499, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5004-7865","authenticated-orcid":false,"given":"Junseong","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5225-1878","authenticated-orcid":false,"given":"Chong Gu","family":"Lee","sequence":"additional","affiliation":[{"name":"Precious Catalysts Inc. 201, Duryu-gil, Angangeup, Gyeongju 38029, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1491-6103","authenticated-orcid":false,"given":"Bun Yeoul","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Molecular Science and Technology, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 16499, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"15375","DOI":"10.1021\/acs.inorgchem.0c02348","article-title":"Chromium Diamino-bis(phenolate) Complexes as Catalysts for the Ring-Opening Copolymerization of Cyclohexene Oxide and Carbon Dioxide","volume":"59","author":"Ambrose","year":"2020","journal-title":"Inorg. 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