Organophilization of Na+-montmorillonite with polyfluorinated alcohols

Modification of Na⁺-montmorillonite with polyfluorinated alcohols was performed. The structure of the modified Na⁺-montmorillonite was studied by derivatography and Fourier IR spectroscopy. The effect of calcite as clay component on the capability for physical and chemical binding of polyfluorinated alcohols was revealed.     

Features of the reaction of polyfluoroalkyl chlorolsulfites with allyl alcohol

Unlike the saturated aliphatic and aromatic alcohols, allyl alcohol under the same conditions reacts with polyfluoroalkyl chlorosulfites to form not ethers, but polyfluorinated alcohols. The exception is polyfluoroalkyl chlorosulfites with the chain length of more than five carbon atoms. Allyl ethers of polyfluorinated alcohols of general formula CH₂=CHCH₂OCH₂(CF₂CF₂)nH (n = 1–3) were obtained, when the reaction proceeded in the presence of potassium carbonate, owing to its participation in a specific orientation of the reaction centers in the resulting intermediate structure, which is easily transformed into allyl ethers of polyfluorinated alcohols.     

Features of reactions of phthalic anhydride with polyfluorinated alcohols

Polyifluoroalkyl mono- and diesters of phthalic acid were obtained by the reaction of phthalic anhydride with polyfluorinated alcohols. The structure of the polyfluoroalkyl phthalates was studied using IR and ¹H, ¹³C NMR spectroscopy. The nature of the associative interactions between cyclohexanone and polyfluorinated alcohols was revealed.     

Synthesis, characterisation and mass spectrometric fragmentation of O-(chlorodifluoroacylated) alcohols

An indirect and uncatalysed esterification of chlorodifluoroacetic acid with polyfluoro and hydrocarbon alcohols has been developed. The method which involves the reaction between sodium chlorodifluoroacetate and alcohols in dimethylformamide (DMF) is particularly facile with polyfluorinated alcohols resulting in esters in 71-85% yield. The esters have been characterised on the basis of ¹H and ¹⁹F NMR and mass spectral data. The electron impact (EI) mass spectrometric fragmentation of these polyfluorinated esters have shown some interesting features which have been substantiated by using tandem mass spectrometry.     

Synthesis of polyfluoroalkyl chlorosulfites and new polyfluoroalkylation reactions with their participation

Regularities were revealed of polyfluoroalkyl chlorosulfites synthesis by reaction of thionyl chloride with associates polyflorinated alcohol-triethylamine and of a new reaction with polyfluorinated alcohols (catalysis by amides), resulting in symmetrical simple polyfluoroalkyl ethers. New polyfluoroalkylation reactions of aliphatic (including polyfluorinated) alicyclic, benzyl alcohols, phenol, carboxylic acids and their salts with polyfluoroalkyl chlorosulfites through substitution of chlorosilfite moiety by halogen, alkoxy- (or polyfluoroalcoxy-), phenoxy-, and acyloxy-groups were studied. Novel synthesis approaches to Foligo- and polymeric materials with new properties were developed.     

An effective synthesis method for secondary fluorinated alcohols via the reaction of esters of polyfluorinated acids with trialkylalanes

Unlike nonfluorinated analogs, complex esters of polyfluorinated acids in reactions with trialkylalanes produce only polyfluorinated secondary alcohols.Department of Fine Organic Synthesis, Institute of Organic Chemistry, Urals Branch, Russian Academy of Sciences, 450054 Ufa. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 10, pp. 2339–2341, October, 1992.     

Synthesis and Use of Partially Fluorinated Dialkyl Ethers Derived from Hexafluoropropylene

A procedure was developed for preparing partially fluorinated dialkyl ethers by the reaction of hexafluoropropylene with aliphatic and polyfluorinated alcohols in the presence of KOH. On treatment with concentrated sulfuric acid, these ethers form alkyl esters of acids, and on treatment with KOH, alkenyl ethers.     

Synthesis of α-chloropolyfluoroalkyl ethers and acetals based on them

α-Chloropolyfluoroalkyl ethers were synthesized by the reaction of polyfluorinated alcohols H(CF₂CF₂) _n CH₂OH (n=1?3) with aliphatic aldehydes (ethanal, propanal, butanal) and hydrogen chloride. Yield of α-chloroethers decreases from 71 to 61% as the number of carbon atoms in the starting reactants increases. α-Chloropolyfluoroalkyl ethers react with polyfluorinated alcohols (n = 1?3) to form acetals in yield of up to 40–61%, and with methanol and ethanol, up to 98%.     

Synthesis of di(polyfluoroalkyl) ethers

New procedures for preparing di(polyfluoroalkyl) ethers by reactions of polyfluoropropyl chlorosulfonites with polyfluorinated alcohols were tested.Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 9, 2004, pp. 1573–1574.Original Russian Text Copyright © 2004 by Rakhimov, Nalesnaya, Vostrikova.     

A multi-component domino reaction for the direct access to polyfunctionalized indoles via intermolecular allylic esterification and indolation

A novel multi-component reaction for the synthesis of polyfunctionalized indoles and bis-indoles has been established. The reaction pathways were controlled by varying enamines with different substitution patterns to give polyfunctionalized indoles and bis-indoles selectively. The reaction proceeds at a fast speed within 15-30 min with water as the major byproduct, which makes work-up convenient.     

Activation of weak nucleophiles: polyfluorocarbamates from polyfluoroalcohols via a fast radical reaction

A new fast radical mechanism has been observed for the reaction of polyfluorinated alcohols and phenylisocyanate, very sensitive to the change of solvents and the concentration of reactants. The acidity of polyfluoroalcohols seems to be responsible for the observed new reactivity and evidences from kinetic studies, electron paramagnetic resonance, cyclic voltammetry, and photostimulation suggest that polyfluoroalkoxy radical is the key intermediate in the chain. To the best of our knowledge, it is the first time that a radical mechanism is described for the preparation of carbamates.     

2-Polyfluoroalkoxy-1,3,2-dioxaphosphorinanes

2-Polyfluoroalkoxy-1,3,2-dioxaphosphorinanes and related phosphocyclic compounds were prepared by alcoholysis of 2-amino-1,3,2-dioxaphosphorinanes with polyfluorinated alcohols. Principal chemical properties of the products were studied. For the first time copper complexes of fluorine-containing normal phosphites were prepared. A difference in the ligation of copper with fluorinated and nonfluorinated phosphites was shown.     

Synthesis of abietinol and dehydroabietinol polyfluoropolyoxaalkylacylates

New polyfluorinated acylates of diterpene alcohols were prepared by reactions of sodium abietinolate and dihydroabietinolate with perfluoro(2-methyl-3-oxahexanoyl), perfluoro(2,5-dimethyl-3,6-dioxanonanoyl), and perfluoro(2,5,8-trimethyl-3,6,9-trioxaundecanoyl) fluorides, and also of abietinol and dehydroabietinol with heptadecafluorononanoic acid in the presence of catalytic amounts of concentrated sulfuric acid.     

Chemical ionization pathways of polyfluorinated chemicals—A connection to environmental atmospheric processes

A systematic mass spectrometry study of an industrially prolific class of polyfluorinated compounds known as telomers was conducted. The study specifically focused upon polyfluorinated alcohols along with corresponding saturated and alpha,beta-unsaturated fluoroacids. Within each class differing fluoroalkyl chain length homologues were investigated, using negative and positive chemical ionization mass spectrometry (NCI and PCI). In the case of the fluoroalcohols, NCI resulted in the production of more elaborate spectra than the other classes. Moreover, it showed the interesting production of HF(2)(-) and the complex of this species, along with F(-), with the parent molecule. These complexes resulted in the formation of the novel H(2)F(3)(-) ion. Results show that there is significant intra-molecular hydrogen bonding that occurs for these compounds, which influences the molecules fragmentation. This bonding will also influence the fate and disposition through environmental processes (e.g., V(P), k(OH), K(OW), K(OA)) which are affected by molecular geometry. Furthermore, there is an increased accumulation and persistence potential for the molecule as a function of the fluorocarbon chain length. We have shown that in conjunction with the use of mass spectroscopy the engertics of environmental processes for polyfluorinated materials can be established.     

Polyfluoroalkyl Chlorosulfites as New Polyfluorinating Agents

The interaction of polyfluorinated alcohols with triethylamine and the kinetics of the reaction of the resulting triethylamine complexes with thionyl chloride were studied, the mechanism of formation of polyfluoroalkyl chlorosulfites was considered, and the optimal reaction conditions were found. The alkylating power of polyfluoroalkyl chlorosulfites was studied in reactions with alkali metal halides (to obtain polyfluorohaloalkanes), in synthesis of acrylic and methacrylic acid esters, and in synthesis of polyfluoroalkyl ethers (with polyfluoroalkyl 1-adamantyl ethers as example).     

Kinetics and mechanism of reaction between polyfluorinated alcohols and thionyl chloride

Complexing of polyfluorinated alcohols with triethylamine was studied by means of microcalorimetry, IR and NMR spectroscopy. The reaction kinetics of these polar complexes with thionyl chloride was investigated using calorimetry of heat fluxes applying mathematical simulation procedure. The second order of nucleophilic substitution reaction of chlorine by polyfluoroalkoxy group was established.Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 11, 2004, pp. 1628–1631.Original Russian Text Copyright © 2004 by Rakhimov, Popov, Vostrikova, Vostrikova, Zauer.     

Hydrogen bonding of aromatic amines in hydroxylic solvents 2. Absorption and emission spectroscopy of substituted 7-aminocoumarins and 7-aminocarbostyrils

The absorption and fluorescence spectra of 7-aminocoumarins and 7-aminocarbostyrils with different degrees of alkylation were studied in 2-propanol (IP), polyfluorinated alcohols and water. The spectral properties of substituted 7-aminocoumarins and 7-aminocarbostyrils in hexafluoro-2-propanol (HFP) are very different from those in 2-propanol due to the strong hydrogen-bonding (HB) interaction between the solute and the solvent (HFP). The spectral behaviour can be explained in terms of the strength of the HB interaction which depends on the degree of alkylation of the amino group and the electron affinity of the electron-accepting moiety. The absorption spectra indicate that a structural change at the amino nitrogen is induced on formation of strong hydrogen bonds.     

Relationship between the morphology and combustibility of fluorinated polyamide composites

The effect that polyfluorinated alcohols immobilized on montmorillonite support exert on structuralmorphological characteristics and combustibility of polymer composites was studied with 1,1,9-trihydroperfluoro- 1-nonanol as example. The relationship between the flame resistance of this heterochain polymer and its morphology was revealed by X-ray diffraction analysis, electron microscopy, DSC, and Fourier IR spectroscopy. This relationship is associated with the reorganization of the crystal and molecular structure under the influence of fluorinated organoclay, ensuring increased degree of crystallinity and redistribution of the fractions of α- and γ-crystalline forms in the polymorphic composition of polycaprolactam, making its supramolecular structure more perfect, and favoring preparation of a fluorinated material of decreased combustibility.

     

Asymmetric synthesis of 1,2-fluorohydrin: iridium catalyzed hydrogenation of fluorinated allylic alcohol

We have developed a simple protocol for the preparation of 1,2-fluorohydrin by asymmetric hydrogenation of fluorinated allylic alcohols using an efficient azabicyclo thiazole-phosphine iridium complex. The iridium-catalyzed asymmetric synthesis of chiral 1,2-fluorohydrin molecules was carried out at ambient temperature with operational simplicity, and scalability. This method was compatible with various aromatic, aliphatic, and heterocyclic fluorinated compounds as well as a variety of polyfluorinated compounds, providing the corresponding products in excellent yields and enantioselectivities.

We have developed a simple protocol for the preparation of 1,2-fluorohydrin by asymmetric hydrogenation of fluorinated allylic alcohols using an efficient azabicyclo thiazole-phosphine iridium complex.     

Fluorinated Sterols Part II: 26,27-polyfluorinated desmosterols

The synthesis of polyfluorinated desmosterols by a Wittig condensation between a steroidal triphenylphosphonium ylid and polyfluorinated acetones is described. The mass spectra of these fluorinated steroids show significant differences from the unsubstituted parent compounds.