{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:56:36Z","timestamp":1760241396539,"version":"build-2065373602"},"reference-count":43,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2018,3,15]],"date-time":"2018-03-15T00:00:00Z","timestamp":1521072000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["PTDC\/QEQ-ERQ\/1648\/2014","PTDC\/QEQ-QIN\/3967\/2014","UID\/QUI \/00100\/2013","FCT\/9701\/25\/10\/2013\/S"],"award-info":[{"award-number":["PTDC\/QEQ-ERQ\/1648\/2014","PTDC\/QEQ-QIN\/3967\/2014","UID\/QUI \/00100\/2013","FCT\/9701\/25\/10\/2013\/S"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Catalysts"],"abstract":"<jats:p>A series of derivative C-scorpionate rhenium complexes, i.e., [ReCl2{NNC(O)C6H5}(Hpz)(PPh3)2] (A) (where Hpz is pyrazole), [ReCl2{NNC(O)C6H5}(Hpz)2(PPh3)] (B), [ReClF{NNC(O)C6H5}(Hpz)2(PPh3)] (C), and their precursor [ReOCl3(PPh3)2] (D), immobilized on 3-aminopropyl-functionalized silica have been prepared and used for neat O2 oxidation of n-hexane and n-heptane mainly to the corresponding alcohols and, in lower amounts, ketones. The supported catalyst C, with fluoro- and diazenido-ligands, exhibits the highest activity for both alkanes (overall turnover numbers (TONs) up to 3.8 \u00d7 103 and 2.5 \u00d7 103, for n-hexane and n-heptane, respectively) and can be reused in consecutive catalytic cycles. Improved conversion was observed after addition of hetero-carboxylate co-catalysts. A free-radical-based mechanism is proposed to explain the product formation.<\/jats:p>","DOI":"10.3390\/catal8030114","type":"journal-article","created":{"date-parts":[[2018,3,15]],"date-time":"2018-03-15T05:11:28Z","timestamp":1521090688000},"page":"114","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Highly Active and Selective Supported Rhenium Catalysts for Aerobic Oxidation of n-Hexane and n-Heptane"],"prefix":"10.3390","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6566-7218","authenticated-orcid":false,"given":"Gopal","family":"Mishra","sequence":"first","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural, Departamento de Engenharia Qu\u00edmica, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal"},{"name":"Materials Laboratory, Chemistry Centre, CQ-VR, University of Tr\u00e1s-os-Montes e Alto Douro (UTAD), 5001-801 Vila Real, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4060-1057","authenticated-orcid":false,"given":"Elisabete","family":"Alegria","sequence":"additional","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural, Departamento de Engenharia Qu\u00edmica, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal"},{"name":"ADEQ, Instituto Superior de Engenharia de Lisboa, Instituto Polit\u00e9cnico de Lisboa, 1959-007 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8323-888X","authenticated-orcid":false,"given":"Armando","family":"Pombeiro","sequence":"additional","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural, Departamento de Engenharia Qu\u00edmica, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5403-9352","authenticated-orcid":false,"given":"Lu\u00edsa","family":"Martins","sequence":"additional","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural, Departamento de Engenharia Qu\u00edmica, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2018,3,15]]},"reference":[{"key":"ref_1","unstructured":"Hodnett, B.K. (2000). Heterogeneous Catalytic Oxidation: Fundamental and Technological Aspects of the Selective and Total Oxidation of Organic Compounds, John Wiley & Sons."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Centi, G., Cavani, F., and Trifiro, F. (2001). Selective Oxidation by Heterogeneous Catalysis, Kluwer Academic\/Plenum Publishers.","DOI":"10.1007\/978-1-4615-4175-2"},{"key":"ref_3","unstructured":"Kroschwitz, J.I. (2014). 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