{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T00:22:06Z","timestamp":1780532526730,"version":"3.54.1"},"reference-count":40,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2020,3,26]],"date-time":"2020-03-26T00:00:00Z","timestamp":1585180800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006769","name":"Russian Science Foundation","doi-asserted-by":"publisher","award":["18-13-00173"],"award-info":[{"award-number":["18-13-00173"]}],"id":[{"id":"10.13039\/501100006769","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002261","name":"Russian Foundation for Basic Research","doi-asserted-by":"publisher","award":["19-29-08005"],"award-info":[{"award-number":["19-29-08005"]}],"id":[{"id":"10.13039\/501100002261","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>In contrast to diradicals connected by alternant hydrocarbons, only a few studies have addressed diradicals connected by nonalternant hydrocarbons and their heteroatom derivatives. Here, the synthesis, structure, and magnetic properties of pyrrole-2,5-diyl\u2013linked bis(nitronyl nitroxide) and bis(iminonitroxide) diradicals are described. The diradicals show characteristic electron spin resonance spectra in dilute glassy solutions, from which conclusions about the presence of distinct conformations, their symmetry, and interspin distance were made. X-ray diffraction analysis of the diradicals revealed that paramagnetic moieties lie in the plane of the pyrrole ring, because of the formation of an intramolecular hydrogen bond, ONO\u2026H\u2212N, with O\u2026H distances of 2.15\u20132.23 \u00c5. The N\u2013O groups participating in the formation of H-bonds have greater bond lengths (~1.29 \u00c5) as compared with nonparticipating groups (~1.27 \u00c5). The nitronyl nitroxide and iminonitroxide diradicals showed an intramolecular antiferromagnetic interaction, with J = \u221277.3 and \u221222.2 cm\u22121, respectively (H = \u22122JS1\u22c5S2).<\/jats:p>","DOI":"10.3390\/molecules25071503","type":"journal-article","created":{"date-parts":[[2020,4,3]],"date-time":"2020-04-03T05:55:16Z","timestamp":1585893316000},"page":"1503","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["(Pyrrole-2,5-Diyl)-Bis(Nitronyl Nitroxide) and-Bis(Iminonitroxide): Specific Features of the Synthesis, Structure, and Magnetic Properties"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1540-7033","authenticated-orcid":false,"given":"Evgeny","family":"Tretyakov","sequence":"first","affiliation":[{"name":"N. N. Vorozhtsov Institute of Organic Chemistry, Siberian Branch of Russian Academy of Sciences, 9 Ac. Lavrentiev Avenue, 630090 Novosibirsk, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anastasia","family":"Tkacheva","sequence":"additional","affiliation":[{"name":"International Tomography Center, Siberian Branch of Russian Academy of Sciences, 3a Institutskaya Str., 630090 Novosibirsk, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Galina","family":"Romanenko","sequence":"additional","affiliation":[{"name":"International Tomography Center, Siberian Branch of Russian Academy of Sciences, 3a Institutskaya Str., 630090 Novosibirsk, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6918-5459","authenticated-orcid":false,"given":"Artem","family":"Bogomyakov","sequence":"additional","affiliation":[{"name":"International Tomography Center, Siberian Branch of Russian Academy of Sciences, 3a Institutskaya Str., 630090 Novosibirsk, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3510-5219","authenticated-orcid":false,"given":"Dmitri","family":"Stass","sequence":"additional","affiliation":[{"name":"V. V. Voevodsky Institute of Chemical Kinetics and Combustion, Siberian Branch of Russian Academy of Sciences, 3 Institutskaya Str., 630090 Novosibirsk, Russia"},{"name":"Novosibirsk State University, 2 Pirogova Str., 630090 Novosibirsk, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexander","family":"Maryasov","sequence":"additional","affiliation":[{"name":"N. N. Vorozhtsov Institute of Organic Chemistry, Siberian Branch of Russian Academy of Sciences, 9 Ac. Lavrentiev Avenue, 630090 Novosibirsk, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7800-5886","authenticated-orcid":false,"given":"Ekaterina","family":"Zueva","sequence":"additional","affiliation":[{"name":"Kazan National Research Technological University, 68 Karl Marx Str., 420015 Kazan, Russia"},{"name":"Kazan Federal University, 18 Kremlyovskaya Str., 420008 Kazan, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Boris","family":"Trofimov","sequence":"additional","affiliation":[{"name":"A. E. Favorsky Institute of Chemistry, Siberian Branch of Russian Academy of Sciences, 1 Favorsky Str., 664033 Irkutsk, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8280-8112","authenticated-orcid":false,"given":"Victor","family":"Ovcharenko","sequence":"additional","affiliation":[{"name":"International Tomography Center, Siberian Branch of Russian Academy of Sciences, 3a Institutskaya Str., 630090 Novosibirsk, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,3,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"281","DOI":"10.1126\/science.1112446","article-title":"Resonating valence-bond ground state in a phenalenyl-based neutral radical conductor","volume":"309","author":"Pal","year":"2005","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"4022","DOI":"10.1002\/anie.200900472","article-title":"Interactive radical dimers in photoconductive organic thin films","volume":"48","author":"Iwasaki","year":"2009","journal-title":"Angew. 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