caa a22 4500 605511012 CHVBK 20210128100648.0 cr unu---uuuuu 210128e20150601xx s 000 0 eng 10.1007/s00894-015-2695-0 doi (NATIONALLICENCE)springer-10.1007/s00894-015-2695-0 Towards thermally stable cyclophanediene-dihydropyrene photoswitches [Elektronische Daten] [Nasir Khan, Nadeem Sheikh, Ather Khan, Ralf Ludwig, Tariq Mahmood, Wajid Rehman, Yasair Al-Faiyz, Khurshid Ayub] Cyclophanediene dihydropyrenes (CPD-DHP) are photochromic compounds because they change their color by irradiation with lights of different color. Potential use of CPD-DHP photoswitch in memory devices requires a very slow thermal return in the dark in the absence of any side reaction. Herein, thermal return of CPDs to DHPs, and an unwanted sigmatropic shift in DHP is studied through density functional theory calculations at (U)B3LYP/6-31+G(d). The thermal return occurs through symmetry forbidden conrotatory electrocyclic reaction. Dimethyl amino CPD-DHP photoswitch pair has the highest activation barrier for electrocyclization and sigmatropic shifts. The lowest activation barrier for symmetry forbidden electrocyclization is observed for GeBr3 functionalized CPD. An unprecedented decomposition pathway involving elimination of the internal substituents is predicted for Cl, Br and SMe functionalized DHPs. This study shows great promise in understanding the Woodward Hoffmann forbidden processes and, in reducing the synthetic efforts toward robust photochromes for memory applications. Springer-Verlag Berlin Heidelberg, 2015 DFT calculations nationallicence Electrocyclization nationallicence Photoswitches nationallicence Rational design nationallicence Sigmatropic rearrangement nationallicence Thermal process nationallicence Khan Nasir Department of Chemistry, COMSATS Institute of Information Technology, 22060, Abbottabad, Pakistan aut Sheikh Nadeem Department of Chemistry, Faculty of Science, King Faisal University, P.O. Box 380, 31982, Al-Ahsa, Saudi Arabia aut Khan Ather Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore, Pakistan aut Ludwig Ralf Institut für Chemie, Physikalische und Theoretische Chemie, Universität Rostock, Dr.-Lorenz-Weg 1, 18059, Rostock, Germany aut Mahmood Tariq Department of Chemistry, COMSATS Institute of Information Technology, 22060, Abbottabad, Pakistan aut Rehman Wajid Department of Chemistry, Hazara University, Mansehra, Pakistan aut Al-Faiyz Yasair Department of Chemistry, Faculty of Science, King Faisal University, P.O. Box 380, 31982, Al-Ahsa, Saudi Arabia aut Ayub Khurshid Department of Chemistry, COMSATS Institute of Information Technology, 22060, Abbottabad, Pakistan aut Journal of Molecular Modeling Springer Berlin Heidelberg 21/6(2015-06-01), 1-11 1610-2940 21:6<1 2015 21 894 https://doi.org/10.1007/s00894-015-2695-0 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00894-015-2695-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Khan Nasir Department of Chemistry, COMSATS Institute of Information Technology, 22060, Abbottabad, Pakistan aut NATIONALLICENCE 700 1- Sheikh Nadeem Department of Chemistry, Faculty of Science, King Faisal University, P.O. Box 380, 31982, Al-Ahsa, Saudi Arabia aut NATIONALLICENCE 700 1- Khan Ather Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore, Pakistan aut NATIONALLICENCE 700 1- Ludwig Ralf Institut für Chemie, Physikalische und Theoretische Chemie, Universität Rostock, Dr.-Lorenz-Weg 1, 18059, Rostock, Germany aut NATIONALLICENCE 700 1- Mahmood Tariq Department of Chemistry, COMSATS Institute of Information Technology, 22060, Abbottabad, Pakistan aut NATIONALLICENCE 700 1- Rehman Wajid Department of Chemistry, Hazara University, Mansehra, Pakistan aut NATIONALLICENCE 700 1- Al-Faiyz Yasair Department of Chemistry, Faculty of Science, King Faisal University, P.O. Box 380, 31982, Al-Ahsa, Saudi Arabia aut NATIONALLICENCE 700 1- Ayub Khurshid Department of Chemistry, COMSATS Institute of Information Technology, 22060, Abbottabad, Pakistan aut NATIONALLICENCE 773 0- Journal of Molecular Modeling Springer Berlin Heidelberg 21/6(2015-06-01), 1-11 1610-2940 21:6<1 2015 21 894