4,4 -Amino-stilbenes

Stilben-4-yl)naphthotriazoles (2) are prepared by diazotization of 4-amino-stilbene-2-sulfonic acid or 4-amino-2-cyano-4 -chlorostilbene, coupling with an ortho-coupling naphthylamine derivative, and finally, oxidation to the triazole. 

Fig. 10.1 Structures ofthe fluorescent whitening agents included in this study. Full names DAS 1,4,4 -bis[4-anilino-6-morpholino-1,3,5-triazin-2-yl)-amino]stilbene-2,2 -disulphonate DSBP, 4,4 -bis(2-sulfostyryl)biphenyl BLS, 4,4 -bis(4-chloro-3-sulfostyryl)biphenyl. Internal standard 4,4 -bis-5-ethyl-3-sulfobenzofur-2-yl)biphenyl.

So-called optical bleaches, such asBlankophor BA, a substituted amino stilbene sulfonic acid, like auramine O will show enhanced fluorescence in viscous media or when bound to polymers. The strong blue emission tends to give the dyed fabric, especially when viewed under sunlight illumination, an apparent whiteness to the fabric. This stilbene derivative is... 

Here, the order of coupling can be nicely illustrated upon varying the stoichiometry of the aryl halide and the reaction conditions. The amination proceeds faster and at lower temperatures than the Heck reaction, as shown by symmetrical N,N-diarylation at 60 °C followed by the Heck vinylations of a second aryl halide at 110 °C to give the amino stilbene derivatives 109 (Scheme 38). 

Even unsymmetrically substituted arylated amino stilbenes 110 can be readily synthesized by reaction of one equivalent of an aryl halide in... 

SYN DISODIUM-4,4 -BIS((4-ANIUNO-6-METHOXY-s-TRIAZIN-2-YL)AMINO)STILBENE-2,2 -DISULFONATE... 

Fig. (4). A combination of 3,4-methylenedioxy-5,4 -dimethoxy-3 -amino-( -stilbene with the des-Doe tetrapeptide unit of the tubulin assembly inhibitor dolastatin 10...

A regioselective carbolithiation of o-amino-( )-stilbenes has been achieved with a series of alkyllithiums when TH F was employed as reaction solvent (Figure 2.9) [60]. High levels of diastereoselectivity have been obtained following the reaction of the lithiated intermediate in TH F with different electrophiles such as MeOD, CO2, and BusSnCl. It was shown that diastereoselectivity was influenced by the orfho-amino substituent and the alkyllithium used for carbolithiation. 

Figure 2.9 A regioselective carbolithiation of o-amino- )-stilbenes [60], (Reproduced with permission.)...

Figure 3.14 Fluorescence emission of frans-4-dimethylamino-4 -amino-stilbene in a free state in 8 x 10 M toluene solution (closed squares) and an immobilized state cross-linked with cyanuric chloride to the coating BSA protein in toluene (open squares) and in glycerin (rhombus) [55], (Reproduced with permission from Elsevier.)...

The electronic spectroscopy of trans-isomers of 3-(N-phenylamino)stilbene (mlc), 3-(N-methyl-N-phenylamino)stilbene (mid), 3-(N,N-diphenylamino)stilbene (mle), and 3-(N-(2,6-dimethylphenyl)amino)stilbene (mlf) and their double-bond constrained analogues, m2a-m2c and m2e, were studied [71]. When compared with trans-3-aminostilbene (mla), mlc-mle displayed a redshift of the So —> Si absorption and fluorescence spectra, lower oscillator strength and fluorescence rate constants, and more effldent Si —> Ti intersystem crossing. The N-Ph derivatives mlc-mle had lower fluorescence quantum yields and higher photoisomerization quantum yields. The role of Si —> Ti transition in the amino-substituted stilbenes as the predominant nonradiative decay pathway was discussed. The excited triplet (Ti) state formation of stilbene dendrimers (tetramethoxystilbene (generation G) GO, Gl,... 

Synthesis and nonlinear optical characterization of a two-photon absorbing organic dye, trans-4-(dimethylamino)-4 -[N-ethyl-N-(2-hydroxyethyl)amino]stilbene (DMAHAS), were reported [49]. Linear absorption, single-photon-induced fluorescence, and two-photon-induced fluorescence of DMAHAS were experimentally studied. This dye showed a moderate two-photon absorption cross section of a2 = 0.91 X 10-46 cm s/photon at 532 nm as shown by an open aperture Z-scan technique. DMAHAS also showed strong two-photon-induced blue fluorescence of 432 nm when pumped with 800 nm laser irradiation. 

A large and rigid hydrophilic sulfhydryl reagent, 4-acetamido-4 -[(iodoacetyl)amino] stilbene-2,2 -disulfonic acid (lASD) disodium salt. 

Chemical name tetrasodium 2-[[4-[bis2-hydroxyethyl) amino]-6-(4-sulphonatoanilino)-1,3,5-triazin-2-yl]amino]stilbene-2,2 -disulpho-nate] ... 

The most familiar derivatives of diaminostilbene disulfonic acid are the 4,4 -bis-(triazinyl-amino)-stilbene disulfonic acids. Compounds of this type are produced by converting one molecule of 4,4 -diaminostilbene-2,2 -disulfonic acid with two molecules of cyanuric chloride (5) to yield compound 6 and then substituting the remaining labile halogen atoms with nonchromophoric substituents such as aUcoxy or phenoxy groups, but generally by means of unsubstituted, substituted, aliphatic, or aromatic amine groups (examples are compounds 7 and 8). 

Three new mainchain chromophoric polymers were synthesized and characterized. The physical properites of these polymers were compared to those of poly((4-N-ethylene-N-ethylamino)-a-cyanocinnamate). Films of the polymers can be made by either solution or melt casting of films. It was possible to obtain an oriented fibw of a polymer, namely poly(4 -[N-ethylene-N-(2-hydroxyethyl)amino] stilbene-4-formate, most likely because it has a melt transition temperature at around 210°C. Nonlinear optical studies of these polymers are in progress. 

DIsodlum 4,4 -bis [[4-anilino-6-(ethylamlno)-1,3,5-trlazln-2-yl] amino] stilbene-2,2 -dlsulfonate Disodium 4,4 -bls [[6-anlllno-4-(ethylamlno)-1,3,5-triazin-2-yl] amino] stllbene-2,2 -disulfonate. See DIsodlum bisethylphenyl trlamino-trlazlne stilbenedlsulfonate... 

Synonyms Benzenesulfonic acid, 2,2 -(1,2-ethenediyl) bis [5-[[4-(ethylamino)-6-(phenylamino)-1,3,5-triazin-2-ylj amino]-, disodium salt Cl fluorescent brightener 208 Disodium 4,4 -bis [[4-anilino-6-(ethylamino)-1,3,5-triazin-2-yl] amino] stil-bene-2,2 -disulfonate Disodium 4,4 -bis [[6-anilino-4-(ethylamino)-1,3,5-triazin-2-yl] amino] stilbene-2,2 -disulfonate 2,2 -(1,2-Ethenediyl) bis (5-(4-(ethylamino)-6-(phenylamino)-l, 3,5-triazin-2-yl) amino) benzenesulfonic acid, disodium salt 2,2 -Stilbenedisulfonic acid, 4,4 -bis ((4-anilino-6-ethylamino-s-triazin-2-yl) amino)-, disodium salt... 

There are, however, certain cyclic diacyl hydrazides which chemiluminesce very poorly in anhydrous DMSO as well as in water, but which, in mixed DMSO/ water solvents, yield a rather strong chemiluminescence, e.g. 3-(2-dialkyl-aminovinyl) phthalhydrazides (see Appendix, p. 205) [44] and trans-4- dialkyl-amino stilbene-2,3-dicarboxylic acid hydrazides [18]. 

Scheme 16 Kinetic vs. thennodynamic control in the lithium-catalyzed cyclization of amino-stilbenes [242]...

Azo-stilbene dyes formed by diazotization of a condensation product containing primary amino groups and coupling with azo dye coupling components, eg. Direct Brown 29 (Cl 40505) (6) ... 

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