{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T15:01:00Z","timestamp":1775746860040,"version":"3.50.1"},"reference-count":68,"publisher":"Wiley","issue":"72","license":[{"start":{"date-parts":[[2025,11,11]],"date-time":"2025-11-11T00:00:00Z","timestamp":1762819200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"},{"start":{"date-parts":[[2025,11,11]],"date-time":"2025-11-11T00:00:00Z","timestamp":1762819200000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["chemistry-europe.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Chemistry A European J"],"published-print":{"date-parts":[[2025,12,23]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>\n                    Due to the lower aromaticity of thiophene compared to benzene, thiophene\u2010based diradicaloid compounds prefer larger weightage of their quinoid form (closed\u2010shell electronic configuration) than their benzoid form (open\u2010shell electronic configuration). At the same time, the lower aromaticity of thiophene facilitates its participation in electrocyclic reactions and as a result dithienylethene\u2010derivatives represent a classical example of photochromism. Here a modular approach for the synthesis of crystalline thienylene\u2010, bithienylene\u2010, and terthienylene\u2010based diradicaloids is reported with acyclic diaminocarbene\u2010scaffold as end\u2010caps. The influence of the\n                    <jats:italic>\u03c0<\/jats:italic>\n                    \u2010conjugated spacer is reflected in their triplet population at room temperature: thienylene\u2010 and bithienylene\u2010bridged diradicaloids are EPR inactive whereas the terthienylene\u2010bridged one exhibits an EPR signal, the intensity of which increases with rising temperature. A dithienylethene\u2010based photochromic bis\u2010amidinium cation was also designed and synthesized to obtain a related thienylene\u2010based diradicaloid. Under two\u2010electron reduction the crystalline diradicaloid is formed with a concurrent reductive ring\u2010closing of the dithienylethene\u2010core. Moreover, a two\u2010electron oxidation of this dithienylethene\u2010based diradicaloid leads to the closed\u2010form of the dithienylethene\u2010based photochromic bis\u2010amidinium cation. Overall, this demonstrates the structurally characterized electrochromic (reductive as well as electron\u2010mediated) ring\u2010closing of a dithienylethene\u2010based photochromic\n                    <jats:italic>\u03c0<\/jats:italic>\n                    \u2010non\u2010conjugated bis\u2010amidinium cation to the diradicaloid and\n                    <jats:italic>\u03c0<\/jats:italic>\n                    \u2010conjugated bis\u2010amidinium cation, establishing an alternative stimulus in place of UV light.\n                  <\/jats:p>","DOI":"10.1002\/chem.202502914","type":"journal-article","created":{"date-parts":[[2025,11,11]],"date-time":"2025-11-11T08:09:08Z","timestamp":1762848548000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Thienylene\u2010Based Diradicaloids: Electrochromic Ring\u2010Closing of Dithienylethene\u2010Based Bis\u2010Amidinium Cation"],"prefix":"10.1002","volume":"31","author":[{"given":"Priyanka","family":"Saha","sequence":"first","affiliation":[{"name":"Tata Institute of Fundamental Research Hyderabad  Gopanpally Hyderabad 500046 India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nicolas","family":"Chrysochos","sequence":"additional","affiliation":[{"name":"Tata Institute of Fundamental Research Hyderabad  Gopanpally Hyderabad 500046 India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Benedict J.","family":"Elvers","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Biochemie Universit\u00e4t Greifswald  Felix\u2010Hausdorff\u2010Stra\u00dfe 4 D\u201017489 Greifswald Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Siva Sankar Murthy","family":"Bandaru","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Biochemie Universit\u00e4t Greifswald  Felix\u2010Hausdorff\u2010Stra\u00dfe 4 D\u201017489 Greifswald Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tejaswinee","family":"Gangber","sequence":"additional","affiliation":[{"name":"Tata Institute of Fundamental Research Hyderabad  Gopanpally Hyderabad 500046 India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Khyati","family":"Gaur","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Organische Chemie Universit\u00e4t zu K\u00f6ln Greinstrasse 4 K\u00f6ln 50939 Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ivo","family":"Krummenacher","sequence":"additional","affiliation":[{"name":"Institute of Inorganic Chemistry and Institute for Sustainable Chemistry &amp; Catalysis with Boron Julius\u2010Maximilians\u2010Universit\u00e4t W\u00fcrzburg  Am Hubland 97074 W\u00fcrzburg Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Holger","family":"Braunschweig","sequence":"additional","affiliation":[{"name":"Institute of Inorganic Chemistry and Institute for Sustainable Chemistry &amp; Catalysis with Boron Julius\u2010Maximilians\u2010Universit\u00e4t W\u00fcrzburg  Am Hubland 97074 W\u00fcrzburg Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vadapalli","family":"Chandrasekhar","sequence":"additional","affiliation":[{"name":"Tata Institute of Fundamental Research Hyderabad  Gopanpally Hyderabad 500046 India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7553-9188","authenticated-orcid":false,"given":"Prince","family":"Ravat","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Organische Chemie Universit\u00e4t zu K\u00f6ln Greinstrasse 4 K\u00f6ln 50939 Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carola","family":"Schulzke","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Biochemie Universit\u00e4t Greifswald  Felix\u2010Hausdorff\u2010Stra\u00dfe 4 D\u201017489 Greifswald Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1657-1321","authenticated-orcid":false,"given":"Anukul","family":"Jana","sequence":"additional","affiliation":[{"name":"Tata Institute of Fundamental Research Hyderabad  Gopanpally Hyderabad 500046 India"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[2025,11,11]]},"reference":[{"key":"e_1_2_5_1_1","doi-asserted-by":"publisher","DOI":"10.1021\/ja960582d"},{"key":"e_1_2_5_2_1","doi-asserted-by":"publisher","DOI":"10.1021\/jp102065g"},{"key":"e_1_2_5_3_1","doi-asserted-by":"publisher","DOI":"10.1021\/acs.chemrev.9b00260"},{"key":"e_1_2_5_4_1","doi-asserted-by":"publisher","DOI":"10.1021\/cr400056a"},{"key":"e_1_2_5_5_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41557-019-0399-2"},{"key":"e_1_2_5_6_1","doi-asserted-by":"publisher","DOI":"10.1039\/D0SC05475E"},{"key":"e_1_2_5_7_1","doi-asserted-by":"publisher","DOI":"10.1039\/C7CC09949E"},{"key":"e_1_2_5_8_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.chempr.2019.02.010"},{"key":"e_1_2_5_9_1","doi-asserted-by":"publisher","DOI":"10.1021\/jacs.9b12683"},{"key":"e_1_2_5_10_1","doi-asserted-by":"publisher","DOI":"10.1039\/C4SC00659C"},{"key":"e_1_2_5_11_1","doi-asserted-by":"publisher","DOI":"10.1002\/anie.201713346"},{"key":"e_1_2_5_12_1","doi-asserted-by":"publisher","DOI":"10.1039\/C8SC01209A"},{"key":"e_1_2_5_13_1","doi-asserted-by":"publisher","DOI":"10.1002\/chem.201804524"},{"key":"e_1_2_5_14_1","doi-asserted-by":"publisher","DOI":"10.1002\/anie.201915802"},{"key":"e_1_2_5_15_1","doi-asserted-by":"publisher","DOI":"10.1021\/acs.joc.1c01827"},{"key":"e_1_2_5_16_1","doi-asserted-by":"publisher","DOI":"10.1002\/chem.202104567"},{"key":"e_1_2_5_17_1","doi-asserted-by":"publisher","DOI":"10.1038\/160403a0"},{"key":"e_1_2_5_18_1","doi-asserted-by":"publisher","DOI":"10.1021\/ja00708a073"},{"key":"e_1_2_5_19_1","doi-asserted-by":"crossref","unstructured":"W. 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These data are provided free of charge by the joint Cambridge Crystallographic Data Center and Fachinformationszentrum Karlsruhe Access Structures service."},{"key":"e_1_2_5_64_1","doi-asserted-by":"publisher","DOI":"10.1021\/jacs.0c12624"},{"key":"e_1_2_5_65_1","doi-asserted-by":"publisher","DOI":"10.1039\/D0SC03622F"},{"key":"e_1_2_5_66_1","unstructured":"Although we have collectively referred to compounds 2a 2b 2c and 5 as thienylene based diradicaloids as they can be presented in both benzoid\u2010 and quinoid\u2010forms their ground\u2010state electronic structure depends on the \u03c0\u2010conjugated spacer."},{"key":"e_1_2_5_67_1","doi-asserted-by":"publisher","DOI":"10.1021\/ja000605v"},{"key":"e_1_2_5_68_1","doi-asserted-by":"publisher","DOI":"10.1016\/0040-4039(90)80143-A"}],"container-title":["Chemistry \u2013 A European Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/chemistry-europe.onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/chem.202502914","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/chemistry-europe.onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/chem.202502914","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/chemistry-europe.onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/chem.202502914","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T14:25:51Z","timestamp":1775744751000},"score":1,"resource":{"primary":{"URL":"https:\/\/chemistry-europe.onlinelibrary.wiley.com\/doi\/10.1002\/chem.202502914"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,11,11]]},"references-count":68,"journal-issue":{"issue":"72","published-print":{"date-parts":[[2025,12,23]]}},"alternative-id":["10.1002\/chem.202502914"],"URL":"https:\/\/doi.org\/10.1002\/chem.202502914","archive":["Portico"],"relation":{},"ISSN":["0947-6539","1521-3765"],"issn-type":[{"value":"0947-6539","type":"print"},{"value":"1521-3765","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,11,11]]},"assertion":[{"value":"2025-10-17","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-11-03","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-11-11","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e02914"}}