2026-05-28T17:56:56Zhttps://riubu.ubu.es/oai/request

oai:riubu.ubu.es:10259/42732022-04-29T12:02:48Zcom_10259_3593com_10259_5086com_10259_2604col_10259_3594

Vicente Poutás, Luis Carlos de 554db1a8-6680-446d-92b4-9ef08d98b3f3 500 Castiñeira Reis, Marta 20b2b122-8570-4fee-be99-a200741eb2e4 500 Sanz Díez, Roberto 531 500 Silva López, Carlos 0ee5b0c9-6148-4e20-8d10-a4196558fb1c 500 Nieto Faza, Olalla . 22ecaaeb-839e-4c87-89aa-1aff3dc73b53 500 2016-11-21T08:04:24Z 2017-11-07T03:45:06Z 2016-11 0020-1669 http://hdl.handle.net/10259/4273 We propose a novel mechanism for the deoxydehydration (DODH) reaction of glycols catalyzed by a [Bu4N][VO2(dipic)] complex (dipic = pyridine-2,6-dicarboxylate) using triphenylphosphine as a reducing agent. Using density functional theory, we have confirmed that the preferred sequence of reaction steps involves reduction of the V(V) complex by phosphine, followed by condensation of the glycol into a [VO(dipic)(-O-CH2CH2-O-)] V(III) complex (6), which then evolves to the alkene product, with recovery of the catalyst. In contrast to the usually invoked closed-shell mechanism for the latter steps, where 6 suffers a [3+2] retrocycloaddition, we have found that the homolytic cleavage of one of the C–O bonds in 6 is preferred by 12 kcal/mol. The resulting diradical intermediate then collapses to a metallacycle that evolves to the product through an aromatic [2+2] retrocycloaddition. We use this key change in the mechanism to propose ways to design better catalysts for this transformation. The analysis of the mechanisms in both singlet and triplet potential energy surfaces, together with the location of the MECPs between them, showcases this reaction as an interesting example of two-state reactivity. Xunta de Galicia and Ministerio de Economiá y Competitividad for funding through Projects EM2014/040 and CTQ2013-48937-C2-1-P and CTQ2013-48937-C2-2-P, respectively. R.S. thanks the Junta de Castilla y León for funding through projects BU237U13 and BU076U16. application/pdf eng American Chemical Society Inorganic chemistry, 2016, V. 5, n 21, p. 11372–11382 http://dx.doi.org/10.1021/acs.inorgchem.6b01916 Chemistry, Organic Química orgánica A Radical Mechanism for the Vanadium-Catalyzed Deoxydehydration of Glycols info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion info:eu-repo/semantics/openAccess THUMBNAIL Vicente-IC-2016.pdf.jpg Vicente-IC-2016.pdf.jpg IM Thumbnail image/jpeg 3531 https://riubu.ubu.es/bitstream/10259/4273/4/Vicente-IC-2016.pdf.jpg 921808b2dbb6675c9e39c204634d62d3 MD5 4 ORIGINAL Vicente-IC-2016.pdf Vicente-IC-2016.pdf application/pdf 2032476 https://riubu.ubu.es/bitstream/10259/4273/1/Vicente-IC-2016.pdf 10dda0d5ab366d1888870b41ec265aa0 MD5 1 LICENSE license.txt license.txt text/plain; charset=utf-8 999 https://riubu.ubu.es/bitstream/10259/4273/2/license.txt b295bcbce42e2caabeb0c623d3860c06 MD5 2 TEXT Vicente-IC-2016.pdf.txt Vicente-IC-2016.pdf.txt Extracted text text/plain 57237 https://riubu.ubu.es/bitstream/10259/4273/3/Vicente-IC-2016.pdf.txt 2b322dbecb9e41c43381355366f18b2b MD5 3 10259/4273 oai:riubu.ubu.es:10259/4273 2022-04-29 14:02:48.029 Repositorio Institucional de la Universidad de Burgos bubrep@ubu.es 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