Rhodamine, synthesis

In the present work, the synthesis of two MIEPs is described and their application for sensing and separation two xanthene dyes - rhodamine and fluorescein - has been reported. 

As an example of a heterocyclic arylcarbonium ion dye, the method of synthesis of Rhodamine B (128) is shown in Scheme 6.3. The starting materials in this case are phthalic anhydride and 3-N,N-die-thylaminophenol. 

Guminski Y, Grousseaud M, Cugnasse S et al (2009) Synthesis of conjugated spermine derivatives with 7-nitrobenzoxadiazole (NBD), rhodamine and bodipy as new fluorescent probes for the polyamine transport system. Bioorg Med Chem Lett 19 2474—2477... 

Beija M, Afonso CAM, Martinho JMG (2009) Synthesis and applications of Rhodamine derivatives as fluorescent probes. Chem Soc Rev 38 2410-2433... 

Guzikowski AP, Naleway JJ, Shipp CT, Schutte RC (2000) Synthesis of a macrocyclic rhodamine 110 enzyme substrate as an intracellular probe for caspase 3 activity. Tetrahedron Lett 41 4733 1735... 

Meng Q, Yu M, Zhang H et al (2007) Synthesis and application of /V-hydroxysuccinimidyl rhodamine B ester as an amine-reactive fluorescent probe. Dyes Pigm 73 254—260... 

Verhaegh, N.A.M., and van Blaaderen, A. (1994) Dispersions of rhodamine-labeled silica spheres synthesis, characterization, and fluorescence confocal scanning laser microscopy. Langmuir 10, 1427-1438. 

Figure 2.14 Influence of the synthesis pH on the release rate of Rhodamine 6G from microparticles. (Reproduced from ref. 7, with permission.)...

Succineins. Succineins are carboxyethyl-substituted pyronines made by substituting succinic anhydride for formaldehyde in the basic synthesis, as, for example, in Basic Red 11 [72968-14-0] (Cl 45050) (Rhodamine S) (16). 

Synthesis of Xanthene Dyes. Phtbalic anhydride reacts with 3-dietbylaminophe-nol in the molten state to give rhodamine B, and with resorcinol to give fluorescein. For unsymmetrical xanthene dyes, dihydroxybenzoyl- (24) or an aminohy-droxybenzoylbenzoic acid (25) is required. 

Cai, S.X. et al. 2001 Design and synthesis of rhodamine 110 derivative andcaspase-3 substrate for enzyme and cell-based fluorescent assay. Bioorg. Med. Chem. Lett. 11, 39-42. 

An interesting approach is a method that uses the modulation of the degree of circular polarization (e.g., between pure 1-cpl and linearly polarized light) to determine fast isomerization kinetics [71]. However, preliminary results on [Co(ox)(phen)2] and rhodamin 6G 14 were not followed by the announced full papers, and the arcticle is rarely cited. In principle the concept may be used to determine interconversion and the CD spectra of rotamers (like 14) which are the reactants in asymmetric synthesis (see Sec. II.C.). 

Molybdates are used in a variety of industries. Sodium molybdate is used for the synthesis of pigments such as molybdate chrome orange, which is a homogeneous mixture of lead molybdate, lead chromate and lead sulphate. This use is likely to decline because of concerns about health hazards associated with lead, but phosphomolybdates and phosphotungstomolybdates are used to complex certain dyestuffs to produce pigments. A few of the best-known of these are Malachite Green, Rhodamine Band Methyl Violet, also used as indicators in analytical chemistry. 

The rotational reorientation times of the sample in several solvents at room temperature were measured by picosecond time-resolved fluorescence and absorption depolarization spectroscopy. Details of our experimental setups were described elsewhere. For the time-correlated single photon counting measurement of which the response time is a ut 40 ps, the sample solution was excited with a second harmonics of a femtosecond Ti sapphire laser (370 nm) and the fluorescence polarized parallel and perpendicular to the direction of the excitation pulse polarization as well as the magic angle one were monitored. The second harmonics of the rhodamine-640 dye laser (313 nm 10 ps FWHM) was used to raesisure the polarized transient absorption spectra. The synthesis of the sample is given elsewhere. All the solvents of spectro-grade were used without further purification. 

R. Hoppe, A. Ortlam, J. Rathousky, G. Schulz-Eklof, and A. Zukal, Synthesis of Titanium-containing MCM-41 Mesoporous Molecular Sieves in the Presence of Zinc Phthalocyanine and Rhodamine B. Microporous Mater., 1997, 8, 267-273. 

The third method to stain the PMMA is to add the fluorescent dye after particle synthesis. This is achieved by finding a solvent that will dissolve the dye and also be taken up by the particles. Thus, an acetone/cyclohexanone mixture can be used to deliver rhodamine perchlorate dye to preformed PMMA spheres [13]. Tire advantage of this method is that once a suitable delivery system is found, many possible dyes, and even multiple dyes, may be added to tire spheres. The disadvantage is that the solvent mixture may attack the spheres, swell them or alter their physical properties. 

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