Excited State N−H Tautomer Selectivity in the Singlet Energy Transfer of a Zinc(II)‐Porphyrin–Truxene–Corrole Assembly. Issue 21 (22nd February 2017)

• Record Type: Journal Article
• Authors: Langlois, Adam; Xu, Hai‐Jun; Karsenti, Paul‐Ludovic; Gros, Claude P.; Harvey, Pierre D.
• Is Part Of: Chemistry. Volume 23:Issue 21(2017)
• Page Start: 5010
• Page End: 5022
• Publication Date: 2017-02-22
• Subjects: corroles -- Dexter energy transfer -- FRET -- tautomerization -- truxene; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201605909
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: An original corrole‐containing polyad for S1 energy transfer, in which one zinc(II)‐porphyrin donor is linked to two free‐base corrole acceptors by a truxene linker, is reported. This polyad exhibits a rapid zinc(II)‐porphyrin*→free‐base corrole transfer (4.83×10 10 s −1 ; 298 K), even faster than the tautomerization in the excited state processes taking advantage of the good electronic communication provided by the truxene bridge. Importantly, the energy transfer process shows approximately 3‐fold selectivity for one corrole N−H tautomer over the other even at low temperature (77 K). This selectivity is due to the difference in the J ‐integral being effective in both the Förster and Dexter mechanisms. The data are rationalized by DFT computations. Abstract : Funneling the excitation energy : The preparation and analysis of a donor (Zn‐porphyrin)–acceptor (free‐base corrole) system, bridged by a truxene spacer, that exhibits a rapid energy transfer (ET) process is reported. The ET is shown to have an effect on the N−H tautomerization of the corrole greatly favoring one tautomer over the other. The ET and tautomerization process are studied by DFT and ultrafast time‐resolved spectroscopy.