Design and photochemical characterization of a biomimetic light-driven Z/E switcher.
Protonated Schiff bases (PSBs) of polyenals constitute a class of light-driven switchers selected by biological evolution that provide model compounds for the development of artificial light-driven molecular devices or motors. In the present paper, our primary target is to show, through combined computational and experimental studies, that it is possible to approach the design of artificial PSBs suitable for such applications. Below, we use the methods of computational photochemistry to design and characterize the prototype biomimetic molecular switchers 4-cyclopenten-2'-enylidene-3,4-dihydro-2H-pyrrolinium and its 5,5'-dimethyl derivative both containing the penta-2,4-dieniminium chromophore. To find support for the predicted behavior, we also report the photochemical reaction path of the synthetically accessible compound 4-benzylidene-3,4-dihydro-2H-pyrrolinium. We show that the preparation and photochemical characterization of this compound (together with three different N-methyl derivatives) provide both support for the predicted photoisomerization mechanism and information on its sensitivity to the molecular environment.
Dipartimento di Chimica, Università di Siena, Via Aldo Moro 2, I-53100 Siena, Italy.
Diego
D
Sampedro
Annapaola
A
Migani
Alessandra
A
Pepi
Elena
E
Busi
Riccardo
R
Basosi
Loredana
L
Latterini
Fausto
F
Elisei
Stefania
S
Fusi
Fabio
F
Ponticelli
Vinicio
V
Zanirato
Massimo
M
Olivucci
D040761:Biomimetic Materials / Q000138:chemical synthesis / Q000737:chemistry*; D003517:Cyclopentanes / Q000737:chemistry; D007097:Imines / Q000737:chemistry; D007536:Isomerism; D008958:Models, Molecular; D008968:Molecular Conformation; D010777:Photochemistry; D011758:Pyrroles / Q000737:chemistry; D012243:Rhodopsin / Q000737:chemistry; D012545:Schiff Bases / Q000737:chemistry*; D013816:Thermodynamics
D003517:Cyclopentanes; D007097:Imines; D011758:Pyrroles; D012545:Schiff Bases; C013231:pyrroline; D012243:Rhodopsin