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A rapid and simple method to estimate volume and density parameters for group of room-temperature ionic liquids (RTILs) and salts is discussed. Some of the common RTILs estimated are imidazolium, pyridinium, pyrrolidinium, tetralkylammonium, and phosphonium-based RTILs.

A hemilabile pyrazolyl-functionalised N-heterocyclic carbene complex of palladium(II) is synthesized. It is an excellent catalyst for Heck and Suzuki cross-coupling reactions in ionic liquids.

The formation, structural, thermal and thermodynamic properties of the first quaternary salts of 4,4'-bi(1,2,4-triazole) or N-4-(1,2,4-triazole)-N-3-(4-methyl-1,2,4-triazole)amine by reaction with nitric or perchloric acid or 5-nitro-tetrazole are described. The melting points, thermal degradation temperatures and the standard heats of formation for compounds with perchlorate as the anion are found to be higher than those of the analogous nitrates, whereas the highest heats of formation are obtained when 5-nitro-tetrazolate is used as the energetic anion.

Energetic salts comprising substituted imidazolium and 1,2,4-triazolium cations and 4,5-dintro imidazolate and 5-nitrotetrazolate anions are synthesized and characterized. It is found that the imidazolate salts are denser but have lower heats of formation than their tetrazolate analogues.

Cyclic and acyclic guanidinium-based salts are synthesized with the help of the quarternization of guanidine derivatives with nitric or perchloric acid or with iodomethane followed by metathesis reaction with silver nitrate, silver perchlorate, or ammonium dinitroamide. Most of the salts exhibited low melting points and good thermal stabilities.

Di(alkyl- and 4,4,4-trifluorobutylimidazolium) quaternary halides of p-tert-butylcalix[4]arene are prepared and characterized. Findings show that the new salts have high thermal stabilities and good solubilities in many solvents and some of them, based on melting point, can be classified as ionic liquids.

Research has been conducted on 1,2,4-triazole. The alkylation of this compound has been carried out, and the results demonstrate that the produced 1-alkyl triazoles have been quaternized via the use of fluorinated alkyl halides under neat reaction conditions.

Research has been conducted on the stable trialkyl(difluoroamino)silane. The synthesis and characterization of this compound have been performed and the use of (difluoroamino)silane as a synthon for introduction of -NF (sub)2 group into electrophilic organic and inorganic substrates is discussed.

Research has been conducted on azoxy compounds. The gas-phase structure of CF (sub)3 N(O)NF investigated via the use of gas-phase electron diffraction study and quantum chemical calculations is described.

Research has been conducted on fluorinated and nonfluorinated alcohols. The interactions of these alcohols with trans-stilbene have been investigated in the presence of electrophilic reagents and the results indicate that these interactions produce alpha-keto ethers which are dependent on the alcohols' fluorination degree and the reaction time.

Results discuss the reactions of alkyl, aryl, and mixed glyoxal hydrates with Deoxofluor leading to the formation of a mixture of meso and racemic polyfluoro- ethers. A mixture of two different glyoxal hydrates reacting with Deoxofluor yield mixed polyfluoroethers. Further, at low concentrations of glyoxal hydrates, difluoroaldehydes or tetrafluoro derivatives are formed.

Research has been conducted on the 2-methyl-2-(1',1',2',2',3',3',4',4'-nonafluoroheptyloxymethyl)-1,3-propanediol. The single-crystal X-ray structure of this compound has been investigated and the details are reported.

The reinvestigation of the molecular structure of the parent molecule N(sub 4)P(sub 4)F(sub 8) by using x-ray diffraction, gas electron diffraction and differential scanning calorimetry is described. The results from each of these measurements support a nonplanar eight-membered ring for N(sub 4)P(sub 4)F(sub 8) that is puckered and that undergoes a phase transition at -74 degrees C.

Research has been conducted on the diketo compounds. The reactions of these compounds with the Deoxofluor have been examined and the results indicate that while reacting with the Deoxofluor alpha-diketones form difluoro derivatives in the presence of the catalytic amount of HF.

Syntheses of 1,3-ansa, spiro and bridged derivatives of tetrameric fluorophosphazene are discussed. In the presence of CsF, the ansa and bridged derivatives are converted to the spiro compound, indicating the higher thermodynamic stability of the latter.

Results reveal that gamma-ketoesters and gamma-diketones serve as precursors to both mono(trifluoromethyl)alcohols and bis(trifluoromethyl)diols as indicated by the cesium fluoride catalyzed trifluoromethylation of various alpha,beta and gamma diketo compounds with (trifluoromethyl)trimethylsilane. The yields of monoaddition and diaddition products are 70-75% and 5-10%, respectively.

A synthesis of polyfluoroalkyl and pyrimidine methyl ethers has been carried out. Experiments include the reactions of trifluoroamine oxide with substituted uracils in the presence of tetrabutylammonium hydroxide.

Research has been conducted on the reactions of iodoperfluoro-3-oxaundecylsulfonyl fluoride with Cu, Zn or Grignard reagent. The production of organometallic species that further reacted with halohydrocarbons is described.

The trifluoromethylations of esters, aldehydes, and ketones with (trifluoromethyl)trimethylsilane has been undertaken with cesium fluoride as catalyst. Carboxylic esters reacted with cesium fluoride at 25 degrees C to produce silyl ether intermediates which can be changed to trifluoromethyl ketones after hydrolysis. Sulfonic, sulfinic and selenic esters were observed to have good reactivity with cesium fluoride resulting in novel trifluoromethylated compounds.

Strong nitrogen acids HN(So(sub2)F)(sub2) and HN(SO(sub2)CF(sub3))(sub2) and their derivatives have important applications. The chemistry of CIN(SO(sub2)F)(sub2) has been extended to fluroalkylation of Hg(n(So(sub2)F)(sub2))(sub2) and synthesis and isolation of perfluoroalkyl-N(SO(sub2)F)(sub2) derivatives.

A study is conducted on the reaction of 1,4,8-triazacycloudecane and 1,5,9-triazacyclododecane with 1,2-dichlorotetrafluorocyclobutene and 1,2-dichlorohexafluorocyclopentene-1. Results show that the triazamacrocyclic amines reacted smoothly in the presence of an organic base to yield the N-substituted products. However, only monomeric products were formed. X-ray diffraction of the new products formed are also discussed.

A study was conducted to characterize novel electrophilic trifluromethylating agents determined from cheap reagents. A 200 MHz nuclear magnetic resonance (NMR) spectrometer was utilized to determine 19F, 1H and 13C NMR spectra while triflate derivatives were determined by an intermolecular condensation reaction. Results indicated that the electrophilic trifluoromethylating potential can be changed by integrating electron-widthdrawing substituents on the benzene rings.

There is a clear reaction of CF3C6F4OC6F4Li5 generated in situ with group 16 elements (S, Se, Te) to form CF3C6F4OC6F4SH (CF3C6F4OC6F4Se)2 and (CF3C6F4OC6F3Te)2/(CF3C6F4OC6F3)2Te. It is possible to react B(OMe)3/H2o27 with CF3C6F4OC6F4Li to obtain the synthesis of CF3C6F4OC6F4OH. Hydrolysis and recovery of the precursor CF3C6F4OC6F4H5 results from the exposure of CF3C6F4OC6F4Li to the atmosphere. The selenophenol CF3C6F4OC6F4SeH that must be created initially in the reaction with selenium is not isolable.

Acyclic tertiary amines such as triethylamine and tri-n-propylamine were used as HCl scavengers in nucleophilic substitution reactions of cyclic chlorocarbaphosphazenes. The acyclic tertiary amines undergo facile C-N bond cleavage and induced regiospecific substitutions in the dialkylamino groups on the ring carbon atoms of carbaphosphazene. Reactions of the lithium salts of fluoro diols resulted in selectively substituted C-Cl bond with silylamines or sodium phenoxide/thiophenoxide.

The reaction of 4-HC6F4OSiMe3 and C6F5OSiMe3 with hexamethyldisilazane led to the synthesis of stable polysubstituted tetrafluoro- and pentafluorophenylsiloxane. The polyfluorinated aromatic sylil ethers exhibited similar reactivity toward electrophiles without altering the nucleophilicity of oxyge during the replacement of para-hydrogen by fluorine. Furthermore, 4-HC6F4OSiMe3 and C6F5OSiMe3 exhibited increasing reactivity toward substituted pentafluorobenzenes due to the C6F6 < C6F5CF3 < C6F5CN < C6F5NO2 order of the substituent.

The treatment of bifunctional trimethylsilyl ethers/dithioethers with N3P3F6 in the presence of CsF catalysts generates five and six membered monospiroflourophosphazenes. The 31P NMR spectra of these derivatives exhibit strong dependence on ring size. The reactions of N3P3F6 with dioxanes at low temperature produce only dangling products. The five membered S-2-O and S-2-S molecules form a twist boat structure in the solid state, and their melting points are higher than those of six membered molecules. The X-ray crystallographic structures of monospiroflourophosphazenes are discussed.

The syntheses and characterization of five to 18-membered heterocyclic ethers containing polyfluoroalkyl pendant chains are described. The fluorinated side chains were introduced via free radical reactions of poly- and perfluoroalkenes with nonhalogenated oxygen-containing heterocycles. The preparation and single-crystal X-ray analysis of lanthanum triflate complexes of 18-crown-6 and 18-crown-6(CF2CFHCF3) are also described.

Reaction between C6F5CH2Br and perfluoro carbonyl compounds in the presence of CsF generate polyfluoro aromatic ethers. X-ray crystal analysis of C6H5CH2OC(CF3)(C6H5)2 indicates that C-O bond distance is consistent with those of perfluorinated ethers. The C...F intramolecular van der Waals contact between C2...F10 is smaller than the sum of van der Waals radii for fluorine and carbon. Twisting the C6F5CH2O group reduces the intramolecular repulsion.

Me3SiCl and Me3SnCl are used as catalysts in the dechlorination process of some N-chlorohydrazines. The silylated group is introduced into the N-chlorohydrazine through a metasynthesis reaction and a corresponding loss of Me3XCl (X = Si, Sn) is occurred. The ultimate product is azaalkene. Stable chlorohydrazines are produced by the reaction of N-trifluoromethyl-N-perfluoroalkyldichlorocarbimides (compound 1) and ClF. A chlorofluorocarbimide is produced from the compound 1 with Me3SnCl as a catalyst.

Reaction of molecules containing active halogens with per- or polyfluoroaromatic siloxanes, in the presence of fluoride ion, generates highly fluorinated mono- and diethers in high yields. In this synthetic methodology polyfluoroaromatic siloxanes function as transfer reagents. The ethers prepared by this method exhibit high thermal and hydrolytic stability.

Reaction of gamma-SO3 with perfluoroalkyl- and polyfluoroalkoxysilanes leads to insertion of gamma-SO3, producing various silyl sulfonates and silyl sulfate esters. This method helps prepare polyfluorinated sulfonic acids in high yields using commercially available precursors. The insertion reaction is absent during the reaction between gamma-SO3 and polyfluoroalkenyltin compound.

Reaction of triorganotin chlorides with Li(2,4,6-(CF3)3C6H2) or (LiOC(CF3)2)2C6F4 produces triorganotin(IV) derivatives of 1,4-bis(perfluoroisopropoxy)tetrafluorobenzene and 2,4, 6-tris(trifluoromethyl)benzene. Single crystal X-ray studies reveal the presence of Sn-F contacts in the solid state, while 19F NMR studies do not support the presence of Sn-F bonding interactions. 119Sn NMR spectroscopy helps analyze the tin-fluorine interactions in the derivatives.

Reaction of acyclic polyfluoro mono and disiloxanes, prepared by the reaction of alcohols with hexamethyldisilazane, with various electrophiles produces stable acyclic and cyclic perfluorinated mono or diethers. Stoichiometry of the reaction regulates the extent of the substitution. Alkaline hydrogen peroxide hydrolyzes the ether to produce the corresponding benzamides.