Under the patronage of the deanery office of the college of pharmacy at UoD, the M.Sc. thesis of the student “Nirozh Azad Chalabi” entitled: “Photochromism and photosynthesis of new chromenis from: newly synthesized Dichloro - Chalcones” has been discussed on 17.12.2020 at cultural center-UoD.
It is worthy to mention that this study has been published in the journal of the University of Duhok.
Link to the journal : https://journal.uod.ac/index.php/uodjournal/index/
This Study was prepared under the supervision of:
- Professor “Dr. Ghazwan Faisal Fadel”
The Scientific Committees were:
- Prof. “Dr. Ahlam Muhammad Nuri Yahya” ... Chairman
- Prof. “Dr. Shereen Rashid Mohamed” ... Member
- Lecturer “Dr. Alia Daoud” ... Member
Abstract
A series of chalcone derivatives (E)-3-(2,6-dichlorophenyl)-1-(4-(dimethylamino)phenyl)prop-2-en-1-one (A1), (E)-3-(2,4-dichlorophenyl)-1-(4-(dimethylamino)phenyl)prop-2-en-1-one(A2), (E)-3-(2,3-dichloro phenyl) -1-(4-(dimethylamino)phenyl)prop-2-en-1-one(A3), (E)-3-(4-chloro phenyl)-1-(4-(dimethylamino)phenyl)prop-2-en-1-one(A4), (E)-3-(2,6-dichlorophenyl)-1-(4-hydroxyphenyl)prop-2-en-1-one(A5), (E)-3-(2,6-dichloro-4-hydroxyphenyl)-1-(4-(dimethylamino)phenyl)prop-2-en-1-one(A6), (E)-3-(2,3-dichlorophenyl)-1-(4-hydroxyphenyl)prop-2-en-1-one(A7), (E)-3-(2,6-dichlorophenyl)-1-(4-nitrophenyl)prop-2-en-1-one(A8) and (2E,2'E)-3,3'-(1,4-phenylene)bis(1-(2,6-dichlorophenyl)prop-2-en-1-one (A9), were synthesized and their structures were confirmed. The chalcones were synthesized by Claisen-Schmidt reaction in presence of aqueous alcoholic alkali solution by condensation of a suitable substituted acetophenone with substituted benzaldehydes. The reactions were followed by thin layer chromatography. All chalcones were characterized by Fourier transform infrared, ultraviolet-visible, 1H and 13C nuclear magnetic resonance spectroscopy and elemental analysis. The photosynthesis of chromenes were accomplished from the irradiation of the corresponding chalcones with xenon light as shown in the scheme below.
All photosynthesized chromenes were characterized by: UV-Visible, FT-IR, 1HNMR, Elemental analysis and liquid chromatography-quadrupole-time-of-flight mass spectrometry (LC-Q-ToF-MS).
All chalcones displayed photochromism phenomenon and the photostationary state was investigated. Hydroxy chalcones were faster than other substituted chalcones to reach the photostationary state after 12 minutes of irradiation. The lmax for the chalcones and chromenes fall in the range (285-389)nm and (485-576)nm respectively in chloroform. The chromenes underwent dark reaction in which the chromene isomerizes back to its precursor chalcone as shown in scheme above.