Gated Photochromism of 1,2-Diarylethenes

Abstract

A dithienylethene derivative containing a cyclobutene-1,2-dione skeleton does not exhibit photochromic properties. However, when both ketone functions are protected with cyclic acetal groups, photochromic behavior is observed.The properties of organic switches have been widely detailed in the literature. 1 One of the main challenges in employing these photochromic compounds for applications in optical memory media is to establish nondestructive readout capability. One of the ways to induce this property is to introduce gated photochromic reactivity into the system.A compound is said to possess the property of gated reactivity if it converts from a photoinert state at a particular wavelength to a photoactive state by the application of external stimuli such as reactive chemicals, 2-6 heat, 7,8 or multiphoton absorption. 9 Several gated diarylethene photochromic systems have been reported. Strategies such as esterification reactions, 2 [4 + 2] cycloaddition reactions, 3 acid/base reactions, 4 redox processes, 6 and hydrogen bondings 6,8 have been employed to manipulate the photochromic reactivity. Previously, a derivative similar to 1a, wherein methyl groups were present in lieu of phenyl substituents, was found to be photoinert. 10 The absence of any photochromic reaction was attributed to the apparent rigidity of the structure. 10 In contrast, cyclobutene-1,2-dione derivatives can perform a photochemical(1) (a) Bouas-Laurent, H.; Durr, H.

Directed synthesis of new spiro-fused photochromes of diarylethene series

“…We should note that only isolated examples of spirofused DAE are known. [31][32][33] However, based on the current data, it is expected that the presence of spiro-fused moiety at the ethene linker could be used to confer certain useful properties to DAE. For example, some of the best forward quantum reaction yields have been demonstrated for spirofused DAE specifically due to the non-covalent interaction, caused by the presence of spirofusion.…”

“…31 By introducing or removing spirofusion it may be possible to tune the ability of DAE to undergo photochromic transformations. 32 The introduction of spirofusion may also be used for the preparation of DAE with several photoswitchable fragments. 33 The presented data show the importance of developing new approaches to the synthesis of diarylethenes featuring a rare combination of structural moieties, in particular spiro-fused systems.…”

“…The assumption that spirofusion at the ethene linker may create obstacles to photochromism in 1,2-dithienyl-substituted DAE was confirmed by literature data. 32 Other examples of molecules with steric contacts between substituents in the aryl group and substituents at the ethene linker also show the absence of photochromism. 44 Thus, we have developed a new method for the synthesis of diarylethenes with spirofusion at ethene linker.…”

Synthesis and photochromism of isomeric unsymmetrical diarylethenes bearing both naphthalene and thiophene moieties

“…In recent years, some studies aiming at the potential application of diarylethenes have focused considerably on the design of diarylethene derivatives with tunable optoelectronic properties [16][17][18][19], and the subsequent investigation into their fundamental properties have contributed to a broad understanding of the photochromism of diarylethenes [20][21][22][23][24]. Generally, the photochromic reactivity of diarylethenes mainly depends on the types of heteroaryl groups and electron donor/acceptor substituents.…”

Synthesis and Properties of a Novel Diarylethene with a Benzene Unit

“…As is well known, studies on the hexatriene backbone of diarylethenes are mainly confined to the five-membered heteroaryl moieties, and the diarylethene designs are generally limited to the addition of functional units to the aryl rings and the substitution of the central ethene group [1,[9][10][11][12]. In the case of six-membered rings as aryl moieties, only a few symmetrical diarylethene derivatives bearing two phenyl/naphthyl groups have been reported [13][14].…”