Electron Transfer from Aliphatic Radicals to Ring-Substituted Pyridine N-Oxides and Their Cobalt−Ammine Complexes in Aqueous Solution
The reduction of pyridine N-oxides by 1-hydroxy-1-methylethyl radicals, •CMe2OH, is acid-dependent, in accord with the greater reducibility of protonated pyridine N-oxides. The respective rate constants for the unprotonated (k R0) and protonated (k R1) pyridine N-oxides have the following values (L...
Gespeichert in:
| Veröffentlicht in: | Inorganic Chemistry 1996-08, Vol.35 (18), p.5168-5172 |
|---|---|
| Hauptverfasser: | , , , , |
| Format: | Artikel |
| Sprache: | eng |
| Schlagworte: | |
| Online-Zugang: | Volltext |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| container_end_page | 5172 |
|---|---|
| container_issue | 18 |
| container_start_page | 5168 |
| container_title | Inorganic Chemistry |
| container_volume | 35 |
| creator | Bakac, A Butković, V Espenson, J. H Lovrić, J Orhanović, M |
| description | The reduction of pyridine N-oxides by 1-hydroxy-1-methylethyl radicals, •CMe2OH, is acid-dependent, in accord with the greater reducibility of protonated pyridine N-oxides. The respective rate constants for the unprotonated (k R0) and protonated (k R1) pyridine N-oxides have the following values (L mol-1 s-1): 8.1 × 107 and 2.8 × 109 (X = 4-CN), 7.5 × 106 and 3.7 × 108 (4-Cl), 7.8 × 106 and 8.4 × 107 (H), and 1.7 × 106 and 4.1 × 107 (4-Me). The reduction of the Co(III) complexes (NH3)5Co(X-pyO)3+ by •CMe2OH is rapid (k = 107−108 L mol-1 s-1) and acid-independent. On the basis of linear free energy relationships it is concluded that the reduction of the Co(III) complexes takes place by a chemical mechanism, whereby •CMe2OH reduces the coordinated X-pyO followed by an intramolecular electron transfer to the cobalt center. |
| doi_str_mv | 10.1021/ic960111s |
| format | Article |
| fullrecord | <record><control><sourceid>acs_osti_</sourceid><recordid>TN_cdi_crossref_primary_10_1021_ic960111s</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><sourcerecordid>c842118992</sourcerecordid><originalsourceid>FETCH-LOGICAL-a253t-b4175cb769af4a715c1e5bf253d09f5799019cf99b1dcba10f83f2a0b7b131893</originalsourceid><addsrcrecordid>eNpt0M1OGzEQB3ALtRJp6IE3MIceOGzr2Y1342O0oh8iAkrSquJi2V67Mezaqe2VwhPQM4_YJ6lRECdOM9L8NKP5I3QM5COQEj5ZxWoCAPEATYCWpKBAfr1BE0JyD3XNDtG7GG8JIaya1RP0cNZrlYJ3eB2Ei0YHbIIf8KK3241IVuFr0Vkl-oiTx9fW_S5Wo4zJpjHpDl_dB9tZp_FFcbmznY5YuA6vN9oG3Hop-vTv7-NiGJ5I64dtr3fZWIcXf0btx4hXvh-T9e4IvTX5iH7_XKfox-ezdfu1WF5--dYuloUoaZUKOYOGKtnUTJiZaIAq0FSaPOsIM7RhjABThjEJnZICiJlXphRENhIqmLNqik72e33-gUdlk1Yb5Z3LKfBZU89pmc3p3qjgYwza8G2wgwj3HAh_Spm_pJxtsbc2Jr17gSLc8bqpGsrXVyu-PL_5fvOzPeer7D_svVCR3_oxuPztK3v_A3AKjcc</addsrcrecordid><sourcetype>Open Access Repository</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype></control><display><type>article</type><title>Electron Transfer from Aliphatic Radicals to Ring-Substituted Pyridine N-Oxides and Their Cobalt−Ammine Complexes in Aqueous Solution</title><source>ACS Publications</source><creator>Bakac, A ; Butković, V ; Espenson, J. H ; Lovrić, J ; Orhanović, M</creator><creatorcontrib>Bakac, A ; Butković, V ; Espenson, J. H ; Lovrić, J ; Orhanović, M</creatorcontrib><description>The reduction of pyridine N-oxides by 1-hydroxy-1-methylethyl radicals, •CMe2OH, is acid-dependent, in accord with the greater reducibility of protonated pyridine N-oxides. The respective rate constants for the unprotonated (k R0) and protonated (k R1) pyridine N-oxides have the following values (L mol-1 s-1): 8.1 × 107 and 2.8 × 109 (X = 4-CN), 7.5 × 106 and 3.7 × 108 (4-Cl), 7.8 × 106 and 8.4 × 107 (H), and 1.7 × 106 and 4.1 × 107 (4-Me). The reduction of the Co(III) complexes (NH3)5Co(X-pyO)3+ by •CMe2OH is rapid (k = 107−108 L mol-1 s-1) and acid-independent. On the basis of linear free energy relationships it is concluded that the reduction of the Co(III) complexes takes place by a chemical mechanism, whereby •CMe2OH reduces the coordinated X-pyO followed by an intramolecular electron transfer to the cobalt center.</description><identifier>ISSN: 0020-1669</identifier><identifier>EISSN: 1520-510X</identifier><identifier>DOI: 10.1021/ic960111s</identifier><language>eng</language><publisher>United States: American Chemical Society</publisher><subject>40 CHEMISTRY ; ALLYL RADICALS ; CHEMICAL REACTION KINETICS ; COBALT COMPLEXES ; ELECTRON TRANSFER ; ORGANIC NITROGEN COMPOUNDS ; ORGANIC OXYGEN COMPOUNDS ; REDUCTION</subject><ispartof>Inorganic Chemistry, 1996-08, Vol.35 (18), p.5168-5172</ispartof><rights>Copyright © 1996 American Chemical Society</rights><lds50>peer_reviewed</lds50><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-a253t-b4175cb769af4a715c1e5bf253d09f5799019cf99b1dcba10f83f2a0b7b131893</citedby><cites>FETCH-LOGICAL-a253t-b4175cb769af4a715c1e5bf253d09f5799019cf99b1dcba10f83f2a0b7b131893</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktopdf>$$Uhttps://pubs.acs.org/doi/pdf/10.1021/ic960111s$$EPDF$$P50$$Gacs$$H</linktopdf><linktohtml>$$Uhttps://pubs.acs.org/doi/10.1021/ic960111s$$EHTML$$P50$$Gacs$$H</linktohtml><link.rule.ids>314,776,780,881,2752,27053,27901,27902,56713,56763</link.rule.ids><backlink>$$Uhttps://www.osti.gov/biblio/476852$$D View this record in Osti.gov$$Hfree_for_read</backlink></links><search><creatorcontrib>Bakac, A</creatorcontrib><creatorcontrib>Butković, V</creatorcontrib><creatorcontrib>Espenson, J. H</creatorcontrib><creatorcontrib>Lovrić, J</creatorcontrib><creatorcontrib>Orhanović, M</creatorcontrib><title>Electron Transfer from Aliphatic Radicals to Ring-Substituted Pyridine N-Oxides and Their Cobalt−Ammine Complexes in Aqueous Solution</title><title>Inorganic Chemistry</title><addtitle>Inorg. Chem</addtitle><description>The reduction of pyridine N-oxides by 1-hydroxy-1-methylethyl radicals, •CMe2OH, is acid-dependent, in accord with the greater reducibility of protonated pyridine N-oxides. The respective rate constants for the unprotonated (k R0) and protonated (k R1) pyridine N-oxides have the following values (L mol-1 s-1): 8.1 × 107 and 2.8 × 109 (X = 4-CN), 7.5 × 106 and 3.7 × 108 (4-Cl), 7.8 × 106 and 8.4 × 107 (H), and 1.7 × 106 and 4.1 × 107 (4-Me). The reduction of the Co(III) complexes (NH3)5Co(X-pyO)3+ by •CMe2OH is rapid (k = 107−108 L mol-1 s-1) and acid-independent. On the basis of linear free energy relationships it is concluded that the reduction of the Co(III) complexes takes place by a chemical mechanism, whereby •CMe2OH reduces the coordinated X-pyO followed by an intramolecular electron transfer to the cobalt center.</description><subject>40 CHEMISTRY</subject><subject>ALLYL RADICALS</subject><subject>CHEMICAL REACTION KINETICS</subject><subject>COBALT COMPLEXES</subject><subject>ELECTRON TRANSFER</subject><subject>ORGANIC NITROGEN COMPOUNDS</subject><subject>ORGANIC OXYGEN COMPOUNDS</subject><subject>REDUCTION</subject><issn>0020-1669</issn><issn>1520-510X</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>1996</creationdate><recordtype>article</recordtype><recordid>eNpt0M1OGzEQB3ALtRJp6IE3MIceOGzr2Y1342O0oh8iAkrSquJi2V67Mezaqe2VwhPQM4_YJ6lRECdOM9L8NKP5I3QM5COQEj5ZxWoCAPEATYCWpKBAfr1BE0JyD3XNDtG7GG8JIaya1RP0cNZrlYJ3eB2Ei0YHbIIf8KK3241IVuFr0Vkl-oiTx9fW_S5Wo4zJpjHpDl_dB9tZp_FFcbmznY5YuA6vN9oG3Hop-vTv7-NiGJ5I64dtr3fZWIcXf0btx4hXvh-T9e4IvTX5iH7_XKfox-ezdfu1WF5--dYuloUoaZUKOYOGKtnUTJiZaIAq0FSaPOsIM7RhjABThjEJnZICiJlXphRENhIqmLNqik72e33-gUdlk1Yb5Z3LKfBZU89pmc3p3qjgYwza8G2wgwj3HAh_Spm_pJxtsbc2Jr17gSLc8bqpGsrXVyu-PL_5fvOzPeer7D_svVCR3_oxuPztK3v_A3AKjcc</recordid><startdate>19960828</startdate><enddate>19960828</enddate><creator>Bakac, A</creator><creator>Butković, V</creator><creator>Espenson, J. H</creator><creator>Lovrić, J</creator><creator>Orhanović, M</creator><general>American Chemical Society</general><scope>BSCLL</scope><scope>AAYXX</scope><scope>CITATION</scope><scope>OTOTI</scope></search><sort><creationdate>19960828</creationdate><title>Electron Transfer from Aliphatic Radicals to Ring-Substituted Pyridine N-Oxides and Their Cobalt−Ammine Complexes in Aqueous Solution</title><author>Bakac, A ; Butković, V ; Espenson, J. H ; Lovrić, J ; Orhanović, M</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-a253t-b4175cb769af4a715c1e5bf253d09f5799019cf99b1dcba10f83f2a0b7b131893</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>1996</creationdate><topic>40 CHEMISTRY</topic><topic>ALLYL RADICALS</topic><topic>CHEMICAL REACTION KINETICS</topic><topic>COBALT COMPLEXES</topic><topic>ELECTRON TRANSFER</topic><topic>ORGANIC NITROGEN COMPOUNDS</topic><topic>ORGANIC OXYGEN COMPOUNDS</topic><topic>REDUCTION</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Bakac, A</creatorcontrib><creatorcontrib>Butković, V</creatorcontrib><creatorcontrib>Espenson, J. H</creatorcontrib><creatorcontrib>Lovrić, J</creatorcontrib><creatorcontrib>Orhanović, M</creatorcontrib><collection>Istex</collection><collection>CrossRef</collection><collection>OSTI.GOV</collection><jtitle>Inorganic Chemistry</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Bakac, A</au><au>Butković, V</au><au>Espenson, J. H</au><au>Lovrić, J</au><au>Orhanović, M</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Electron Transfer from Aliphatic Radicals to Ring-Substituted Pyridine N-Oxides and Their Cobalt−Ammine Complexes in Aqueous Solution</atitle><jtitle>Inorganic Chemistry</jtitle><addtitle>Inorg. Chem</addtitle><date>1996-08-28</date><risdate>1996</risdate><volume>35</volume><issue>18</issue><spage>5168</spage><epage>5172</epage><pages>5168-5172</pages><issn>0020-1669</issn><eissn>1520-510X</eissn><abstract>The reduction of pyridine N-oxides by 1-hydroxy-1-methylethyl radicals, •CMe2OH, is acid-dependent, in accord with the greater reducibility of protonated pyridine N-oxides. The respective rate constants for the unprotonated (k R0) and protonated (k R1) pyridine N-oxides have the following values (L mol-1 s-1): 8.1 × 107 and 2.8 × 109 (X = 4-CN), 7.5 × 106 and 3.7 × 108 (4-Cl), 7.8 × 106 and 8.4 × 107 (H), and 1.7 × 106 and 4.1 × 107 (4-Me). The reduction of the Co(III) complexes (NH3)5Co(X-pyO)3+ by •CMe2OH is rapid (k = 107−108 L mol-1 s-1) and acid-independent. On the basis of linear free energy relationships it is concluded that the reduction of the Co(III) complexes takes place by a chemical mechanism, whereby •CMe2OH reduces the coordinated X-pyO followed by an intramolecular electron transfer to the cobalt center.</abstract><cop>United States</cop><pub>American Chemical Society</pub><doi>10.1021/ic960111s</doi><tpages>5</tpages></addata></record> |
| fulltext | fulltext |
| identifier | ISSN: 0020-1669 |
| ispartof | Inorganic Chemistry, 1996-08, Vol.35 (18), p.5168-5172 |
| issn | 0020-1669 1520-510X |
| language | eng |
| recordid | cdi_crossref_primary_10_1021_ic960111s |
| source | ACS Publications |
| subjects | 40 CHEMISTRY ALLYL RADICALS CHEMICAL REACTION KINETICS COBALT COMPLEXES ELECTRON TRANSFER ORGANIC NITROGEN COMPOUNDS ORGANIC OXYGEN COMPOUNDS REDUCTION |
| title | Electron Transfer from Aliphatic Radicals to Ring-Substituted Pyridine N-Oxides and Their Cobalt−Ammine Complexes in Aqueous Solution |
| url | https://sfx.bib-bvb.de/sfx_tum?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2025-02-05T12%3A13%3A51IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-acs_osti_&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=Electron%20Transfer%20from%20Aliphatic%20Radicals%20to%20Ring-Substituted%20Pyridine%20N-Oxides%20and%20Their%20Cobalt%E2%88%92Ammine%20Complexes%20in%20Aqueous%20Solution&rft.jtitle=Inorganic%20Chemistry&rft.au=Bakac,%20A&rft.date=1996-08-28&rft.volume=35&rft.issue=18&rft.spage=5168&rft.epage=5172&rft.pages=5168-5172&rft.issn=0020-1669&rft.eissn=1520-510X&rft_id=info:doi/10.1021/ic960111s&rft_dat=%3Cacs_osti_%3Ec842118992%3C/acs_osti_%3E%3Curl%3E%3C/url%3E&disable_directlink=true&sfx.directlink=off&sfx.report_link=0&rft_id=info:oai/&rft_id=info:pmid/&rfr_iscdi=true |