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Excited-state intramolecular proton transfer of 2-acetylindan-1,3-dione studied by ultrafast absorption and fluorescence spectroscopy.

ABSTRACT: We employ transient absorption from the deep-UV to the visible region and fluorescence upconversion to investigate the photoinduced excited-state intramolecular proton-transfer dynamics in a biologically relevant drug molecule, 2-acetylindan-1,3-dione. The molecule is a ß-diketone which in the electronic ground state exists as exocyclic enol with an intramolecular H-bond. Upon electronic excitation at 300?nm, the first excited state of the exocyclic enol is initially populated, followed by ultrafast proton transfer (?160 fs) to form the vibrationally hot endocyclic enol. Subsequently, solvent-induced vibrational relaxation takes place (?10 ps) followed by decay (?390 ps) to the corresponding ground state.

SUBMITTER: Verma PK

PROVIDER: S-EPMC4720111 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature

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Excited-state intramolecular proton transfer of 2-acetylindan-1,3-dione studied by ultrafast absorption and fluorescence spectroscopy.

Verma Pramod Kumar PK Steinbacher Andreas A Schmiedel Alexander A Nuernberger Patrick P Brixner Tobias T

Structural dynamics (Melville, N.Y.) 20151208 2

We employ transient absorption from the deep-UV to the visible region and fluorescence upconversion to investigate the photoinduced excited-state intramolecular proton-transfer dynamics in a biologically relevant drug molecule, 2-acetylindan-1,3-dione. The molecule is a ß-diketone which in the electronic ground state exists as exocyclic enol with an intramolecular H-bond. Upon electronic excitation at 300 nm, the first excited state of the exocyclic enol is initially populated, followed by ultra ...[more]

PMID: 26798837

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