title: Synthesis and detailed spectroscopic characterization of various hydroxy-functionalized fluorescent chalcones: A combined experimental and theoretical study.
abstract: Four different bright yellow to orange hydroxy-substituted chalcones (i.e., 2',4-di-hydroxy (1), 2',3',4-trihydroxy (2), 2',3',4'-trihydroxy (3), and 2'-hydroxy-4-methoxy (4) chalcones) were synthesized and characterized by LC-MS, FT-IR, FT-Raman, and fluorescence spectroscopy and thermogravimetric analysis. UV-visible absorption spectroscopy was also used. The experimental (theoretical) bandgaps of 1, 2, 3, and 4 are 2.89 (2.90), 2.93 (2.95), 3.04 (3.09), and 3.01 (2.91) eV, respectively. The hydroxy-substituted chalcones exhibited strong dual emissions as a consequence of the locally excited states followed by internal charge transfer processes. The molecular structures, lowest energy transitions, vibrational frequencies, and spectroscopic information were calculated using density functional theory and time-dependent density functional theory methods at the B3LYP/6-31G(d,p) theoretical level. The experimental and theoretical data were compared and the relationship between them was briefly discussed.
authors.affiliation: Department of Chemistry and Chemical Institute of Functional Materials, Pusan National University, Busan 609-735, Republic of Korea.
authors.forename: M
authors.initials: M
authors.lastname: Jagadeesh
authors.affiliation: Department of Chemistry, Sri Venkateswara University, Tirupati 517502, Andhra Pradesh, India.
authors.forename: M
authors.initials: M
authors.lastname: Lavanya
authors.affiliation: Department of Surgery, Montreal General Hospital, McGill University, Montreal, Canada.
authors.forename: B
authors.initials: B
authors.lastname: Hari Babu
authors.affiliation: Department of Chemistry and Chemical Institute of Functional Materials, Pusan National University, Busan 609-735, Republic of Korea.
authors.forename: Kiryong
authors.initials: K
authors.lastname: Hong
authors.affiliation: Department of Chemistry and Chemical Institute of Functional Materials, Pusan National University, Busan 609-735, Republic of Korea.
authors.forename: Rory
authors.initials: R
authors.lastname: Ma
authors.affiliation: Department of Chemistry, The Catholic University of Korea, Bucheon 420-743, Republic of Korea. Electronic address: joonghankim@catholic.ac.kr.
authors.forename: Joonghan
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Chemistry and Chemical Institute of Functional Materials, Pusan National University, Busan 609-735, Republic of Korea. Electronic address: tkkim@pusan.ac.kr.
authors.forename: Tae Kyu
authors.initials: TK
authors.lastname: Kim
mesh_terms: D047188:Chalcones / Q000138:chemical synthesis* / Q000737:chemistry*; D002853:Chromatography, Liquid; D005453:Fluorescence; D017665:Hydroxyl Radical / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008958:Models, Molecular; D008962:Models, Theoretical; D008968:Molecular Conformation; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D014732:Vibration
chemical_list: D047188:Chalcones; D017665:Hydroxyl Radical
keywords: DFT calculations; HOMO–LUMO; Hydroxy-substituted chalcones; Vibrational spectra