{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T11:17:19Z","timestamp":1787224639461,"version":"build-2736575974"},"reference-count":57,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2020,10,24]],"date-time":"2020-10-24T00:00:00Z","timestamp":1603497600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000038","name":"Natural Sciences and Engineering Research Council of Canada","doi-asserted-by":"publisher","award":["2016-4905"],"award-info":[{"award-number":["2016-4905"]}],"id":[{"id":"10.13039\/501100000038","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Donor-acceptor Stenhouse adducts (DASAs) are a novel class of solvatochromic photoswitches with increasing importance in photochemistry. Known for their reversibility between open triene and closed cyclized states, these push-pull molecules are applicable in a suite of light-controlled applications. Recent works have sought to understand the DASA photoswitching mechanism and reactive state, as DASAs are vulnerable to irreversible \u201cdark switching\u201d in polar protic solvents. Despite the utility of fluorescence spectroscopy for providing information regarding the electronic structure of organic compounds and gaining mechanistic insight, there have been few studies of DASA fluorescence. Herein, we characterize various photophysical properties of two common DASAs based on Meldrum\u2019s acid and dimethylbarbituric acid by fluorescence spectroscopy. This approach is applied in tandem with complexation by cyclodextrins and cucurbiturils to reveal the zwitterionic charge separation of these photoswitches in aqueous solution and the protective nature of supramolecular complexation against degradative dark switching. DASA-M, for example, was found to form a weak host-guest inclusion complex with (2-hydroxypropyl)-\u03b3-cyclodextrin, with a binding constant K = 60 M\u22121, but a very strong inclusion complex with cucurbit[7]uril, with K = 27,000 M\u22121. This complexation within the host cavity was found to increase the half-life of both DASAs in aqueous solution, indicating the significant and potentially useful stabilization of these DASAs by host encapsulation.<\/jats:p>","DOI":"10.3390\/molecules25214928","type":"journal-article","created":{"date-parts":[[2020,10,26]],"date-time":"2020-10-26T03:51:47Z","timestamp":1603684307000},"page":"4928","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Photophysical Properties of Donor-Acceptor Stenhouse Adducts and Their Inclusion Complexes with Cyclodextrins and Cucurbit[7]uril"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6185-7214","authenticated-orcid":false,"given":"Liam","family":"Payne","sequence":"first","affiliation":[{"name":"Department of Chemistry, University of Prince Edward Island, Charlottetown, PE C1A 4P3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7643-5797","authenticated-orcid":false,"given":"Jason D.","family":"Josephson","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biochemistry, University of Regina, Regina, SK S4S 0A2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8346-2846","authenticated-orcid":false,"given":"R. Scott","family":"Murphy","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biochemistry, University of Regina, Regina, SK S4S 0A2, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1951-0209","authenticated-orcid":false,"given":"Brian D.","family":"Wagner","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Prince Edward Island, Charlottetown, PE C1A 4P3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1910","DOI":"10.1039\/C7CS00772H","article-title":"The (photo)chemistry of Stenhouse photoswitches: Guiding principles and system design","volume":"47","author":"Lerch","year":"2018","journal-title":"Chem. Soc. 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