{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:03:26Z","timestamp":1760058206879,"version":"build-2065373602"},"reference-count":30,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2025,3,24]],"date-time":"2025-03-24T00:00:00Z","timestamp":1742774400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The preparation of two 1-acyl-8-pyrrolylnaphthalenes (5 and 6) and one pyrrolone (8) are reported along with the issues complicating the preparations of other compounds. The photophysical behavior of the fused, planar derivative 6 is explored in detail. The fluorescence of 6 shows solvato-chromism due to intramolecular charge transfer in the excited state and enhanced emission in protic solvents. The emission intensity increases very linearly with the H-bond-donating strength of the solvent. Preferential solvation studies, multilinear regression analysis and computational modeling suggest that the fluorescence enhancement results from inhibition of the spin\u2013orbit coupling-promoted intersystem crossing from the \u03c0\u2192\u03c0* singlet state to an n\u2192\u03c0* triplet state. Some of the inhibitions are due to the dielectric stabilization of the excited singlet state. A stronger effect is obtained from H-bonding, which not only further stabilizes the singlet state but also negatively impacts the vibronic coupling between the states.<\/jats:p>","DOI":"10.3390\/molecules30071429","type":"journal-article","created":{"date-parts":[[2025,3,24]],"date-time":"2025-03-24T04:48:18Z","timestamp":1742791698000},"page":"1429","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Peri-Substituted Acyl Pyrrolyl Naphthalenes: Synthesis, Reactions and Photophysical Properties"],"prefix":"10.3390","volume":"30","author":[{"given":"Junkai","family":"Zhao","sequence":"first","affiliation":[{"name":"Department of Chemistry, College of William and Mary, Williamsburg, VA 23185, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8712-0288","authenticated-orcid":false,"given":"Robert","family":"Pike","sequence":"additional","affiliation":[{"name":"Department of Chemistry, College of William and Mary, Williamsburg, VA 23185, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0123-8390","authenticated-orcid":false,"given":"Christopher","family":"Abelt","sequence":"additional","affiliation":[{"name":"Department of Chemistry, College of William and Mary, Williamsburg, VA 23185, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3075","DOI":"10.1021\/bi00581a025","article-title":"Synthesis and Spectral Properties of a Hydrophobic Fluorescent Probe: 6-Propionyl-2-(Dimethylamino) Naphthalene","volume":"18","author":"Weber","year":"1979","journal-title":"Biochemistry"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"10938","DOI":"10.1021\/jp036013r","article-title":"Does PRODAN Possess a Planar or Twisted Charge-Transfer Excited State? 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