{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T13:04:09Z","timestamp":1790255049475,"version":"4.1.0"},"reference-count":33,"publisher":"American Chemical Society (ACS)","issue":"38","license":[{"start":{"date-parts":[[2026,9,14]],"date-time":"2026-09-14T00:00:00Z","timestamp":1789344000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000165","name":"Division of Chemistry","doi-asserted-by":"publisher","award":["CHE-1011959"],"award-info":[{"award-number":["CHE-1011959"]}],"id":[{"id":"10.13039\/100000165","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000165","name":"Division of Chemistry","doi-asserted-by":"publisher","award":["CHE-2245738"],"award-info":[{"award-number":["CHE-2245738"]}],"id":[{"id":"10.13039\/100000165","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,9,24]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>The photochemistry of 2-benzo[b]thienyl diazomethane (1) and 3-benzo[b]thienyl diazomethane (3), matrix-isolated in Ar or N2 at 10 K, was studied by IR, UV\/vis, and EPR spectroscopy. Although the corresponding 2- and 3-benzo[b]thienyl carbenes (16, 17) were not observed, several interesting rearrangement products (C9H6S isomers) were characterized by IR and UV\/vis spectroscopy. 2-Benzo[b]thienyl diazomethane (1) undergoes ring expansion (\u03bb &amp;gt; 534 nm) to form the strained allene 5,6-benzo-1-thiacyclohexa-2,3-diene (8). 3-Benzo[b]thienyl diazomethane (3) undergoes cyclization (\u03bb &amp;gt; 472 nm) to form 2-thia-3,4-benzobicyclo[3.1.0]-hexa-3,5-diene (13). Irradiation of 13 (\u03bb = 340 nm \u00b1 10 nm) results in ring-opening to form a dark purple quinoid thione intermediate (19), which reverts to cyclopropene 13 upon visible light irradiation (\u03bb = 540 nm \u00b1 10 nm). Structural assignments were confirmed by isotope labeling and comparison of experimental spectra with those predicted using anharmonic density functional theory calculations.<\/jats:p>","DOI":"10.1021\/acs.jpca.6c04620","type":"journal-article","created":{"date-parts":[[2026,9,14]],"date-time":"2026-09-14T17:02:06Z","timestamp":1789405326000},"page":"7687-7695","source":"Crossref","is-referenced-by-count":0,"title":["Photochemistry\nand Spectroscopy of 2- and 3-Benzo[\n                    <i>b<\/i>\n                    ]thienyl\nDiazomethane"],"prefix":"10.1021","volume":"130","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-2800-2393","authenticated-orcid":true,"given":"Laura A.","family":"Kopff","sequence":"first","affiliation":[{"name":"University of Wisconsin-Madison , , 1101 University Avenue , , ,","place":["Madison, Wisconsin, United States, 53706-1322"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9385-8078","authenticated-orcid":true,"given":"Brian J.","family":"Esselman","sequence":"additional","affiliation":[{"name":"University of Wisconsin-Madison , , 1101 University Avenue , , ,","place":["Madison, Wisconsin, United States, 53706-1322"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1377-5107","authenticated-orcid":true,"given":"Robert J.","family":"McMahon","sequence":"additional","affiliation":[{"name":"University of Wisconsin-Madison , , 1101 University Avenue , , ,","place":["Madison, Wisconsin, United States, 53706-1322"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,9,14]]},"reference":[{"key":"2026092408080865200_cit1","first-page":"824","volume-title":"Methoden der Organischen\nChemie (Houben-Weyl)","author":"Wentrup","year":"1989"},{"key":"2026092408080865200_cit2","doi-asserted-by":"crossref","DOI":"10.1007\/978-1-4899-3707-0","volume-title":"Kinetics\nand Spectroscopy of Carbenes and Biradicals","author":"Platz","year":"1990"},{"key":"2026092408080865200_cit3","doi-asserted-by":"publisher","first-page":"1583","DOI":"10.1021\/cr00020a009","article-title":"Carbenes in\nMatrices - Spectroscopy,\nStructure, and Reactivity","volume":"93","author":"Sander","year":"1993","journal-title":"Chem. Rev."},{"key":"2026092408080865200_cit4","volume-title":"Reactive\nIntermediate Chemistry","author":"Moss","year":"2004"},{"key":"2026092408080865200_cit5","doi-asserted-by":"publisher","first-page":"7179","DOI":"10.1021\/cr400150a","article-title":"Heteroarylcarbenes","volume":"113","author":"Sheridan","year":"2013","journal-title":"Chem. 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Chem."},{"key":"2026092408080865200_cit9","doi-asserted-by":"publisher","first-page":"1427","DOI":"10.1016\/S0040-4039(00)91638-1","article-title":"Pyridylhalocarbenes\nand Pyridiniumhalocarbenes","volume":"33","author":"Moss","year":"1992","journal-title":"Tetrahedron Lett."},{"key":"2026092408080865200_cit10","doi-asserted-by":"publisher","first-page":"233","DOI":"10.1021\/ja973550e","article-title":"Stereochemical Effects\nin Carbene Photochemistry: 2-Furylchlorocarbene","volume":"120","author":"Khasanova","year":"1998","journal-title":"J. Am. Chem. Soc."},{"key":"2026092408080865200_cit11","doi-asserted-by":"publisher","first-page":"1091","DOI":"10.1021\/ol990890r","article-title":"Photoselection of Carbene Stereoisomers with Surprisingly\nDifferent Electronic Spectra: 3-Furylchlorocarbene","volume":"1","author":"Khasanova","year":"1999","journal-title":"Org. Lett."},{"key":"2026092408080865200_cit12","doi-asserted-by":"publisher","first-page":"134","DOI":"10.1002\/chin.199038146","article-title":"Generation and trapping of thiophen-2-ylchlorocarbenes from 2-dichloromethylthiophenes\nand 3-chloro-3-(thiophen-2-yl)diazirine","author":"Baird","year":"1990","journal-title":"J.\nChem. Res., Synop."},{"key":"2026092408080865200_cit13","doi-asserted-by":"publisher","first-page":"773","DOI":"10.1016\/S0040-4039(02)02698-9","article-title":"2-Thienylchlorocarbene: reactivity\ntoward alkenes","volume":"44","author":"Moss","year":"2003","journal-title":"Tetrahedron Lett."},{"key":"2026092408080865200_cit14","doi-asserted-by":"publisher","first-page":"8585","DOI":"10.1021\/ja002281g","article-title":"Photochemistry of\n2-Benzofurylchlorocarbene: Characterization\nof a 2,3-Didehydro-2H-pyran","volume":"122","author":"Khasanova","year":"2000","journal-title":"J. Am. Chem. 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See experimental\nsection for details."},{"key":"2026092408080865200_cit27","doi-asserted-by":"publisher","first-page":"1316","DOI":"10.1021\/jo00358a029","article-title":"Benzobicyclo[4.1.0]hepta-2,4,6-trienes","volume":"51","author":"West","year":"1986","journal-title":"J. Org. Chem."},{"key":"2026092408080865200_cit28","doi-asserted-by":"publisher","first-page":"3544","DOI":"10.1021\/jp993496j","article-title":"Spectroscopic Characterization of Matrix-Isolated Phenylcarbene and\nCycloheptatetraene","volume":"104","author":"Matzinger","year":"2000","journal-title":"J. Phys. Chem. A"},{"key":"2026092408080865200_cit29","unstructured":"Pharr, C. R.\n          \n          Spectroscopic\nCharacterization of Triplet (2- and 3-Thienyl)carbenes and Development,\nImplementation, and Testing of a Web-based Tool for use in Middle\nand High School Classrooms. Ph.D. Dissertation. University of Wisconsin-Madison: Madison, WI, 2008."},{"key":"2026092408080865200_cit30","doi-asserted-by":"publisher","first-page":"855","DOI":"10.1021\/ja00056a005","article-title":"Photoequilibration of 2-Naphthylcarbene and 2,3-Benzobicyclo[4.1.0]hepta-2,4,6-triene","volume":"115","author":"Albrecht","year":"1993","journal-title":"J. Am. Chem. Soc."},{"key":"2026092408080865200_cit31","doi-asserted-by":"publisher","first-page":"10496","DOI":"10.1021\/ja9920157","article-title":"Photoequilibration of 1-Naphthylcarbene and 4,5-Benzobicyclo[4.1.0]hepta-2,4,6-triene","volume":"121","author":"Bonvallet","year":"1999","journal-title":"J. Am. Chem. Soc."},{"key":"2026092408080865200_cit32","doi-asserted-by":"publisher","first-page":"9332","DOI":"10.1021\/ja001291e","article-title":"Generation, Characterization, and Rearrangements of\n4,5-Benzocyclohepta-1,2,4,6-tetraene","volume":"122","author":"Bonvallet","year":"2000","journal-title":"J. Am.\nChem. Soc."},{"key":"2026092408080865200_cit33","doi-asserted-by":"publisher","first-page":"9031","DOI":"10.1021\/jo020304z","article-title":"Access to the Naphthylcarbene\nRearrangement Manifold via Isomeric Benzodiazocycloheptatrienes","volume":"67","author":"Bonvallet","year":"2002","journal-title":"J. Org. Chem."}],"container-title":["The Journal of Physical\nChemistry A"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pubs.acs.org\/doi\/pdf\/10.1021\/acs.jpca.6c04620","content-type":"application\/pdf","content-version":"vor","intended-application":"unspecified"},{"URL":"https:\/\/pubs.acs.org\/jpcafh\/article-pdf\/130\/38\/7687\/68503685\/acs.jpca.6c04620.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/pubs.acs.org\/jpcafh\/article-pdf\/130\/38\/7687\/68503685\/acs.jpca.6c04620.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T12:30:32Z","timestamp":1790253032000},"score":1,"resource":{"primary":{"URL":"https:\/\/pubs.acs.org\/jpcafh\/article\/130\/38\/7687\/5429611\/Photochemistry-and-Spectroscopy-of-2-and-3-Benzo-b"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,14]]},"references-count":33,"journal-issue":{"issue":"38","published-online":{"date-parts":[[2026,9,14]]},"published-print":{"date-parts":[[2026,9,24]]}},"URL":"https:\/\/doi.org\/10.1021\/acs.jpca.6c04620","relation":{},"ISSN":["1089-5639","1520-5215"],"issn-type":[{"value":"1089-5639","type":"print"},{"value":"1520-5215","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,14]]}}}