Twisted 8-Acyl-1-dialkyl-amino-naphthalenes Emit from a Planar Intramolecular Charge Transfer Excited State
Fluorescence from dialkylamino donor–acyl acceptor substituted 1,8-naphthalene derivatives can occur either from a planar (PICT) or a twisted (TICT) intramolecular charge transfer excited state. The photophysical properties of 8-acetyl-1-(dimethyl-amino)naphthalene (<b>3</b>) and 8-pival...
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| Format: | Article |
| Language: | English |
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MDPI AG
2024-01-01
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| Series: | Photochem |
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| Online Access: | https://www.mdpi.com/2673-7256/4/1/1 |
| _version_ | 1797239684174184448 |
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| author | Christopher Abelt Kirsten Sweigart |
| author_facet | Christopher Abelt Kirsten Sweigart |
| author_sort | Christopher Abelt |
| collection | DOAJ |
| description | Fluorescence from dialkylamino donor–acyl acceptor substituted 1,8-naphthalene derivatives can occur either from a planar (PICT) or a twisted (TICT) intramolecular charge transfer excited state. The photophysical properties of 8-acetyl-1-(dimethyl-amino)naphthalene (<b>3</b>) and 8-pivaloyl-1-(dimethyl-amino)naphthalene (<b>4</b>) are compared with 1-methyl-2,3-dihydronaphtho[1,8-bc]azepin-4(1H)-one (<b>5</b>). In <b>3</b> and <b>4</b>, both the carbonyl and amino groups are forced to twist out of the plane of the naphthalene ring. In <b>5</b>, these groups are nearly coplanar with the naphthalene. Neither <b>3</b> nor <b>4</b> fluoresce as strongly as <b>5</b>, but all three show similar degrees of solvato-chromism and all are strongly quenched by alcohol solvents. Nitrile <b>6</b>, 8-cyano-1-(dimethyl-amino)naphthalene, does not show the same degree of solvato-chromism as <b>3</b>–<b>5</b>, nor is it as affected by alcohols. Calculations corroborate the experimental results, indicating that <b>3</b>–<b>5</b> emit from a PICT excited state. |
| first_indexed | 2024-04-24T17:55:27Z |
| format | Article |
| id | doaj.art-c5ae9c3e5c3a4957ac2a306a61e318d9 |
| institution | Directory Open Access Journal |
| issn | 2673-7256 |
| language | English |
| last_indexed | 2024-04-24T17:55:27Z |
| publishDate | 2024-01-01 |
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| record_format | Article |
| series | Photochem |
| spelling | doaj.art-c5ae9c3e5c3a4957ac2a306a61e318d92024-03-27T13:59:57ZengMDPI AGPhotochem2673-72562024-01-014111310.3390/photochem4010001Twisted 8-Acyl-1-dialkyl-amino-naphthalenes Emit from a Planar Intramolecular Charge Transfer Excited StateChristopher Abelt0Kirsten Sweigart1Department of Chemistry, College of William and Mary, Williamsburg, VA 23185, USAIndependent Researcher, Northbrook, IL 60062, USAFluorescence from dialkylamino donor–acyl acceptor substituted 1,8-naphthalene derivatives can occur either from a planar (PICT) or a twisted (TICT) intramolecular charge transfer excited state. The photophysical properties of 8-acetyl-1-(dimethyl-amino)naphthalene (<b>3</b>) and 8-pivaloyl-1-(dimethyl-amino)naphthalene (<b>4</b>) are compared with 1-methyl-2,3-dihydronaphtho[1,8-bc]azepin-4(1H)-one (<b>5</b>). In <b>3</b> and <b>4</b>, both the carbonyl and amino groups are forced to twist out of the plane of the naphthalene ring. In <b>5</b>, these groups are nearly coplanar with the naphthalene. Neither <b>3</b> nor <b>4</b> fluoresce as strongly as <b>5</b>, but all three show similar degrees of solvato-chromism and all are strongly quenched by alcohol solvents. Nitrile <b>6</b>, 8-cyano-1-(dimethyl-amino)naphthalene, does not show the same degree of solvato-chromism as <b>3</b>–<b>5</b>, nor is it as affected by alcohols. Calculations corroborate the experimental results, indicating that <b>3</b>–<b>5</b> emit from a PICT excited state.https://www.mdpi.com/2673-7256/4/1/1solvato-chromismcharge transferPICTTICTperi |
| spellingShingle | Christopher Abelt Kirsten Sweigart Twisted 8-Acyl-1-dialkyl-amino-naphthalenes Emit from a Planar Intramolecular Charge Transfer Excited State Photochem solvato-chromism charge transfer PICT TICT peri |
| title | Twisted 8-Acyl-1-dialkyl-amino-naphthalenes Emit from a Planar Intramolecular Charge Transfer Excited State |
| title_full | Twisted 8-Acyl-1-dialkyl-amino-naphthalenes Emit from a Planar Intramolecular Charge Transfer Excited State |
| title_fullStr | Twisted 8-Acyl-1-dialkyl-amino-naphthalenes Emit from a Planar Intramolecular Charge Transfer Excited State |
| title_full_unstemmed | Twisted 8-Acyl-1-dialkyl-amino-naphthalenes Emit from a Planar Intramolecular Charge Transfer Excited State |
| title_short | Twisted 8-Acyl-1-dialkyl-amino-naphthalenes Emit from a Planar Intramolecular Charge Transfer Excited State |
| title_sort | twisted 8 acyl 1 dialkyl amino naphthalenes emit from a planar intramolecular charge transfer excited state |
| topic | solvato-chromism charge transfer PICT TICT peri |
| url | https://www.mdpi.com/2673-7256/4/1/1 |
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