Cristian Guerra, Yeray A. Rodríguez-Núñez, Manuel E. Taborda-Martínez, Mitchell Bacho, Rafael Miranda-Pastrana and Adolfo E. Ensuncho
{"title":"Theoretical exploration of the 4π-photocyclization mechanism of α-tropone derivatives†","authors":"Cristian Guerra, Yeray A. Rodríguez-Núñez, Manuel E. Taborda-Martínez, Mitchell Bacho, Rafael Miranda-Pastrana and Adolfo E. Ensuncho","doi":"10.1039/D4NJ03442B","DOIUrl":null,"url":null,"abstract":"<p >In this study, we employed <em>ab initio</em> methods to investigate the 4π-photocyclization process of substituted α-tropones. Our findings suggest that the initial stages of this reaction occur from low-energy excited states such as S<small><sub>2</sub></small> and S<small><sub>3</sub></small>, as the barriers in higher-energy excited states are prohibitively high. Additionally, we observed that the presence of acid catalysts or substitution of tropones with electron-donating groups reduces the energy barriers. Regarding the formation of bicyclo[3.2.0]hepta-3,6-dien-2-one derivatives, both T<small><sub>1</sub></small>/S<small><sub>0</sub></small> and S<small><sub>1</sub></small>/S<small><sub>0</sub></small> crossings were identified as plausible pathways for this deactivation process. Specifically, electron-donating groups on the tropones promote degeneracy between S<small><sub>1</sub></small> and S<small><sub>0</sub></small> states during the return to the ground state. Moreover, T<small><sub>1</sub></small>/S<small><sub>0</sub></small> crossing systems were consistently observed across all investigated scenarios.</p>","PeriodicalId":95,"journal":{"name":"New Journal of Chemistry","volume":null,"pages":null},"PeriodicalIF":2.7000,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"New Journal of Chemistry","FirstCategoryId":"92","ListUrlMain":"https://pubs.rsc.org/en/content/articlelanding/2024/nj/d4nj03442b","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
In this study, we employed ab initio methods to investigate the 4π-photocyclization process of substituted α-tropones. Our findings suggest that the initial stages of this reaction occur from low-energy excited states such as S2 and S3, as the barriers in higher-energy excited states are prohibitively high. Additionally, we observed that the presence of acid catalysts or substitution of tropones with electron-donating groups reduces the energy barriers. Regarding the formation of bicyclo[3.2.0]hepta-3,6-dien-2-one derivatives, both T1/S0 and S1/S0 crossings were identified as plausible pathways for this deactivation process. Specifically, electron-donating groups on the tropones promote degeneracy between S1 and S0 states during the return to the ground state. Moreover, T1/S0 crossing systems were consistently observed across all investigated scenarios.