Fluorous label

Fluorous chemistry, involving the use of a fluorous label for the functionalization of a substrate and a fluorous solvent for extraction of the functionalized substrate, is shown to be effective in solubilizing gold and CdSe nanoparticles in a fluorous medium, through phase transfer from an aqueous or a hydrocarbon medium. While these nanoparticles were functionalized with a fluorous thiol, single-walled carbon nanotubes and ZnO nanorods could be solubilized in a fluorous medium by reacting them with a fluorous amine. Fluorous chemistry enables the solubilization of the nanostructures in the most nonpolar liquid medium possible. 

In conclusion, we have successfully demonstrated that, by using a fluorous label and a fluorous solvent, we can affect the phase transfer of gold and CdSe nanoparticles from an aqueous or hydrocarbon medium to the fluorous phase. Single-walled carbon nanotubes and ZnO nanorods can be solubilized in a fluorous solvent after interaction with a fluorous amine. Phase transfer of the nanostructures to a fluorous solvent represents solubilization in a highly nonpolar solvent, accompanied by purification. The high nonpolarity of the fluorocarbon makes it possible to study the optical and other properties of nanostructures in a medium of very low refractive index. Since the fluorocarbon extracts only the species attached to the fluorous label, the process enables one to obtain solely one product in the pure state. We believe that fluorous chemistry may have practical utility in carrying out studies of nanostructures. 

Mcintee, J. W. and Valliant, J. F. (2007) Expanding the utility of the fluorous labeling method. Trialkylstannylation of functionalized aryl and vinyl halides with a fluorous distannane. J Labeled Comp. Radiopharm., 50, S198. 

Fluorous synthesis has certain analogies to solid-phase synthesis the fluorous label and the fluorous phase fulfil functions similar to those of the linker and the solid phase in that both provide a means of removing the attached compound from the reaction mixture (one because of its high affinity to the fluorous phase, the other via a covalent link to the solid support).The similarity, however, also extends to the necessity of additional synthesis steps involved in the attachment to and cleavage from the linker. Otherwise, the fluo-... 

Recently, fluorous chemistry has been used to solubilize and phase-transfer nanocrystals of metals (Au) and chalcogenides (CdS) as well as inorganic nanorods (ZnO) [551]. Here, a fluorous label (e.g. fluorinated alkane thiol) is attached to the nanostructures which are then readily extracted by a fluorocarbon from aquous or hydrocarbon solutions, due to fluorine-fluorine interaction. This method not only enables the purification of the nanostructures, but also helps one to study them in the most-nonpolar medium possible, the refractive index of fluorocarbon being around 1.2. 

Isoxazolines and isoxazoles have been prepared in good yield and excellent purity by reaction of excess nitrile oxide and fluorous labelled silyl ether and silyl propargyl ether respectively [29] (Figure 13). Fluorous variants of the Ugi and Biginelli reaction have also been developed [30]. 

Dissolve the peptide RKRSRAE (0.25 mg) in 35 pL of water andmixwith 15 pLofl.OMTEAB (pH 8.5). Add the isotope-coded fluorous labeling reagents (3-H4, 3-D4) (0.9 equiv.) in 50 pL of DMF, and incubate the resulting mixture at room temperature with shaking for 40 min (. Note 13). 

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