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1,5-Prodan Emits from a Planar Intramolecular Charge-Transfer Excited State.

ABSTRACT: 1-Propionyl-5-dimethylaminonaphthalene (8, 1,5-Prodan) and two derivatives where the amino group is constrained in a seven-membered (9) and five-membered (10) ring are prepared. All three exhibit strong fluorescence and similar degrees of solvatochromism. Their fluorescence is strongly quenched in alcohol solvents. Because the amino group in 9 and especially 10 is forced to be coplanar with the naphthalene ring, the similar photophysical behavior of all three suggests that emission arises from a planar excited state (planar intramolecular charge transfer).

SUBMITTER: Chen T

PROVIDER: S-EPMC6641964 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

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1,5-Prodan Emits from a Planar Intramolecular Charge-Transfer Excited State.

Chen Tao T Lee Samuel W SW Abelt Christopher J CJ

ACS omega 20180502 5

1-Propionyl-5-dimethylaminonaphthalene (8, 1,5-Prodan) and two derivatives where the amino group is constrained in a seven-membered (9) and five-membered (10) ring are prepared. All three exhibit strong fluorescence and similar degrees of solvatochromism. Their fluorescence is strongly quenched in alcohol solvents. Because the amino group in 9 and especially 10 is forced to be coplanar with the naphthalene ring, the similar photophysical behavior of all three s ...[more]

PMID: 31458698

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