Photochromic dihetarylethenes

Krayushkin, M. M.; Kalik, M. A.; Dzhavadov, D. L.; Воронцова, Л. Г.; Starikova, Z. A.; Martynkin, A. Yu.; Иванов, В. Л.; Uzhinov, B. M.

doi:10.1007/bf02496349

Cited by 5 publications

(5 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Dibromo compound 4d (1.94 g, 78.5%) was obtained of bp 110-120°C/10 mm Hg, n D 20 1.6000, which was used for further syntheses. 1 H NMR spectrum (CDCl 3 ), δ, ppm (J, Hz): 1.27 (3H, t, J = 7.10, CH 3 CH 2 ); 2.72 (2H, q, J = 7.10, CH 2 CH 3 ); 6.85 (1H, s, H-4) corresponding to the data of [4].…”

Section: Methodsmentioning

confidence: 99%

“…A convenient starting material for these purposes was the mono-substitution product of perfluorocyclopentene, 1-(2-ethyl-5-ethylthio-3-thienyl)heptafluorocyclopentene (3). We note that dibromide 4d [4], necessary for its synthesis and described by us previously [4], was obtained successfully in higher yield (~80%) on using a bromide-bromate mixture as brominating agent. The unsymmetrical dithienylPFCP 2a-c were obtained by the interaction of 1-(2-ethyl-5-ethylthio-3-thienyl)PFCP (3) with the appropriate bromides 4a-c.…”

mentioning

confidence: 99%

mentioning

confidence: 99%

“…We noticed that the presence of alkylthio groups in positions 2 or 5 of the thiophene rings activates the thiophene ring in electrophilic substitution and metallation reactions, which facilitates the subsequent introduction of various substituents into the free positions of the heterocycle. The series of photochromes 1 with substituents in the 4 and 4' positions of the thiophene rings was obtained for the first time by the functionalization of compound 1b [4].Unsymmetrical alkylthio-substituted PFCP have been synthesized in the present work having substituents of various nature in the thiophene rings, containing alkylthio groups either in the reaction center of one of the thiophene rings (product 2a) or in position 5 (products 2b-e) (Scheme 2), and their photochromic properties have been investigated. A convenient starting material for these purposes was the mono-substitution product of perfluorocyclopentene, 1-(2-ethyl-5-ethylthio-3-thienyl)heptafluorocyclopentene (3).…”

mentioning

confidence: 99%

See 3 more Smart Citations

Photochromic Dihetarylethylenes. 22. Synthesis and Photochromic Properties of Unsymmetrical Alkylthio-substituted 1,2-Bis(dithienyl)perfluorocyclopentenes

Krayushkin

Kalik

Kozhinov

et al. 2005

Chem Heterocycl Compd

Self Cite

View full text Add to dashboard Cite

Certain unsymmetrical 1,2-bis(dithienyl)perfluorocyclopentenes have been synthesized containing alkylthio, bromo, carboxy, and benzothiazolyl substituents in the thiophene rings. It was shown that on irradiation with UV light they all display photochromic properties, with the exception of the derivative containing an alkylthio group in the reaction center of one of the thiophene rings.Previously we synthesized vicinally substituted perfluorocyclopentenes (PFCP) 1a,b in which the fluorinated ring was linked symmetrically with thienyl rings bearing alkyl and alkylthio groups (Scheme 1) [2,3]. We noticed that the presence of alkylthio groups in positions 2 or 5 of the thiophene rings activates the thiophene ring in electrophilic substitution and metallation reactions, which facilitates the subsequent introduction of various substituents into the free positions of the heterocycle. The series of photochromes 1 with substituents in the 4 and 4' positions of the thiophene rings was obtained for the first time by the functionalization of compound 1b [4].Unsymmetrical alkylthio-substituted PFCP have been synthesized in the present work having substituents of various nature in the thiophene rings, containing alkylthio groups either in the reaction center of one of the thiophene rings (product 2a) or in position 5 (products 2b-e) (Scheme 2), and their photochromic properties have been investigated. A convenient starting material for these purposes was the mono-substitution product of perfluorocyclopentene, 1-(2-ethyl-5-ethylthio-3-thienyl)heptafluorocyclopentene (3). We note that dibromide 4d [4], necessary for its synthesis and described by us previously [4], was obtained successfully in higher yield (~80%) on using a bromide-bromate mixture as brominating agent. The unsymmetrical dithienylPFCP 2a-c were obtained by the interaction of 1-(2-ethyl-5-ethylthio-3-thienyl)PFCP (3) with the appropriate bromides 4a-c.

show abstract

Section: Methodsmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Photochromic Dihetarylethylenes. 22. Synthesis and Photochromic Properties of Unsymmetrical Alkylthio-substituted 1,2-Bis(dithienyl)perfluorocyclopentenes

Krayushkin

Kalik

Kozhinov

et al. 2005

Chem Heterocycl Compd

Self Cite

View full text Add to dashboard Cite

show abstract

“…We have synthesized and studied 1,2-bis (4methoxy-carbonyl-2-ethen -5 -ethylthiothien-3-yl)hexafluorocyclo-pentene (5) in which all hydrogen atoms of heterocycles are substituted (Scheme 6) [23]. As it was shown by X-ray diffraction analysis the conformation of molecule 5A has some peculiarities in comparison with previously considered structures.…”

Section: The Distance Between Reaction Centers At C(2) • • • C (2)mentioning

confidence: 96%

The structure and characteristics of photochromic dithienylethenes

Krayushkin

Воронцова

Uzhinov

2001

International Journal of Photoenergy

Self Cite

View full text Add to dashboard Cite

The data on X-ray diffraction analysis for dihetarylethenes with perfluorocyclopentene (F), maleic anhydride (M) and cyclobutenedione (S) bridges between thienyl fragments were summarized and their photochromic properties were discussed. It was established that benzoxazole and benzothiazole substituents in position 5 of thienyl rings are coplanar to the plane of thiophene cycles. Thienyl fragments in A form of all dithienylethenes are considerably turned relative to the plane of bridging cycle. It means that there is no conjugation betweenπ-electrons of aromatic heterocycles and double bond of the bridge.Flattening of molecule frameworkand the envelope conformation of thienyl cycles because of aromaticity loss are characteristic features of the form B structure with F-bridge. In all cases (excluding the compounds with alkylthio substituents in position 2 of thiophene cycle) the photochromic transitionA→Bis observed independently of different nature and structure of functional groups.

show abstract

ChemInform Abstract: Photochromic Dihetarylethenes. Part 5. Synthesis, Structure, and Photochromic Properties of 4,4′‐Disubstituted 1,2‐Bis[2‐ethyl‐5‐ethylthio(ethylsulfonyl)‐3‐thienyl] perfluorocyclopentenes.

et al. 2001

View full text Add to dashboard Cite

A series of new photochromic compounds were obtained tbr the first t+me from 1,2-his(2-ethy]thio-3-thienyl)perfluorocyctopentene by substi~ttting bromine atoms or carboxy. alkoxycarbonyt, and carbamoyl groups for hydrogen atoms m positions 4 and 4'. Introduction of these sub~tituent'~ causes a slight bathochromic shift [b~. 20--30 nm) of a long-wavelength :~bsorption band R~ the cyclic form and significantly increases the quantum yields of photocycfization tD A.,B and ring opening ~bs~, ,. Depending on Ihe nature of a substituent. d~.~..+t ~ decreases in the. order COOH > COOMe > CONHAr. The quantum yields are markedly reduced when the cthylthio groups in posinons 5 and 5" are replaced hy eth,dsultbnu groups (a tenfold reduction in 4~a.,B and a tbur-to fiveibtd reduction m %a-,.x)-The most considerable bathochromic shift of a long-wavelength band and the highest quantum yields of totward and reverse photoreacfions were obsewed for 1,2-bist4-bromo-2-ethyl-5-ethyhi~io-3-thienyl)perllunrocyclopentenc. 1, perfluorocyclopemene was qruclurafly characterized b.v X-ray diffraction analysis.

show abstract

Photochromic dihetarylethenes

Cited by 5 publications

References 7 publications

Photochromic Dihetarylethylenes. 22. Synthesis and Photochromic Properties of Unsymmetrical Alkylthio-substituted 1,2-Bis(dithienyl)perfluorocyclopentenes

Photochromic Dihetarylethylenes. 22. Synthesis and Photochromic Properties of Unsymmetrical Alkylthio-substituted 1,2-Bis(dithienyl)perfluorocyclopentenes

The structure and characteristics of photochromic dithienylethenes

ChemInform Abstract: Photochromic Dihetarylethenes. Part 5. Synthesis, Structure, and Photochromic Properties of 4,4′‐Disubstituted 1,2‐Bis[2‐ethyl‐5‐ethylthio(ethylsulfonyl)‐3‐thienyl] perfluorocyclopentenes.

Contact Info

Product

Resources

About