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The cover image depicts the hazard caused by chlorofluorocarbons such as CFC‐11, which are used, for example, as blowing agents for polyurethane foams, and the protective effect of the oligosaccharide, hexakis‐(2,3,6‐tri‐O‐methyl)‐α‐cyclodextrin, which is capable of binding CFC‐11 by supramolecular complexation and thus protecting the stratospheric ozone layer from the harmful trichlorofluoromethane. Further details can be found in article number 1800057 by Ralf Hellmann, Siegfried R. Waldvogel, and co‐workers.

Phase behaviors of high molecular weight polyethylene solutions with hydrocarbons, halogenated hydrocarbons, and oxygen-containing hydrocarbons and their mixture as solvents were examined under high temperature and high pressure, especially near the critical and supercritical condition of the solvent. The pressure temperature (P,T) cloud point curves for polyethylene in pentane, trichlorofluoromethane, and hexane were measured at different compositions. The pressure composition (P,C) cloud point curves at 473 K are presented for three systems. The P,T cloud point curves for volume fraction, ϕ = 2 %, of high molecular weight polyethylene were measured in different hydrocarbons and halogenated hydrocarbons. It was found that the cloud point pressures of the solutions have good correlation with the critical temperature (Tc) of solvents. The P,T cloud point curves for ϕ = 2 % of high molecular weight polyethylene were measured in different hydrocarbon and pentane mixtures, different halogenated hydrocarbon an...

Later-stage spinodal decomposition (SD) of polymer solutions (polypropylene/trichlorofluoromethane) after the onset of pressure jump was investigated in situ by using time-resolved light scattering. The time evolution of the scaled structure factor F(x) ≡ q m (t,P) 3 I(x) with x ≡ q/q m (t,P) was analyzed as a function of time t at various pressure P's where q m (t,P) is the magnitude of scattering vector q at maximum scattered intensity at t and P. In the late-stage SD, F(x) becomes universal with time, indicating that the phase-separated structure grows with self-similarity in the late-stage SD. The obtained F(x) was compared with those of other experiments on polymer blends and computer simulations.

Later-stage spinodal decomposition (SD) of polymer solutions (polypropylene/trichlorofluoromethane) induced by pressure-jump was examined in situ as a function of pressure P by using time-resolved light scattering method with the cell designed for high pressure and high temperature. The time-evolution of the magnitude of scattering vector q m ( t , P ) at maximum scattered intensity and the maximum scattered intensity I m ( t , P ) were analyzed in order to characterize the coarsening processes of the later-stage SD, where t refers to time after the onset of pressure-jump. The changes in q m ( t , P ) and I m ( t , P ) with t at different P 's were found to fall onto the respective master curves on the reduced plots, indicating that the scaling postulate is valid not only for the coarsening behaviors at different temperatures but for those at different P 's.

A new general catalytic olefination reaction (COR) of aromatic and heteroaromatic aldehydes and ketones was applied to synthesise 2-chloro-2-fluorostyrenes. The two-stage procedure includes the transformation of carbonyl compounds into hydrazones followed by treatment with CFCl3 mediated by copper catalysis. Trichlorofluoromethane was used as a chlorofluoromethylene transfer reagent. The reaction proceeds stereoselectively and the target alkenes were obtained in high yield. A proposed mechanism for the reaction is discussed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

It was observed that the reaction of CFCl3 with thiophenoxide gave only 10% of the corresponding thioether. On the other hand, these thioethers could be prepared in excellent yield from diaryl disulfides and CFCl3 in the presence of sodium hydroxymethanesulfinate in aqueous DMF at 4 atm pressure of nitrogen. Dechlorination of the thioether (PhSCFCl2) with different reducing agents were studied. Most of the reducing agents eliminated both fluorine and chlorine functionalities or gave the hydrolyzed products. But its sulfone on treatment with Zinc in methanol gave monochlorofluoromethyl and fluoromethyl phenyl sulfone in good yields. Darzens reaction of these compounds was also studied.

Copolymerization of tetrafluoroethylene and ethylene was investigated in trichlorotrifluoroethane and trichlorofluoromethane solvents. The high solubility of the monomers in these solvents made polymerization under reduced pressures possible. Trichlorofluoromethane acted as an effective chain transfer agent to regulate the molecular weight. Kinetic studies showed that bimolecular and unimolecular termination prevailed at low and high polymer concentrations, respectively.

The insulation efficiency of polyurethane foam is mainly (60 to 65%) determined by the thermal conductivity of the cell gas, which is a mixture of carbon dioxide (CO 2 ) and a blowing agent. Until recently CFC-11 (trichlorofluoromethane) was the most widely used blowing agent. To find adequate substitutes for CFC-11, the vapor-phase thermal conductivity of several potential blowing agents has been measured. The experimental procedure is based on the transient hot-wire method. The apparatus was designed in cooperation with the University of Stuttgart (Prof. K. Stephan). The measuring cell (stainless steel, 1.4571) with a length of 270 mm and a diameter of 48 mm consists of two parallel chambers with platinum wires of different lengths. In this paper experimental results for the vapor-phase thermal conductivity of carbon dioxide (CO 2 ), 1,1,1,2,2-pentafluoropropane (HFC-245cb), 1,1,1,3,3-pentafluoropropane (HFC-245fa), and 1,1,2,2,3-pentafluoropropane (HFC-245ca) are given. Experiments have been performed at pressures between 0.2 MPa and 1.5 MPa and temperatures between 298 K and 419.91 K.

Early stage spinodal decomposition (SD) of polymer solutions (polypropylene/trichlorofluoromethane) induced by pressure jump was investigated with a light scattering instrument designed for polymer solutions under high pressure and high temperature. The changes in the scattered intensity with time at the early stage SD were found to be approximated by Cahn linearized theory or Cahn−Hilliard−Cook theory. The analyses with the theories yielded the characteristic parameters such as the interdiffusion coefficient Dapp and the characteristic wavenumber qm(0). Unlike other experiments on the polymer solutions, the pressure dependence of the parameters was found to obey the mean field behavior. This may be because the quench depth conditions attained by the pressure jump were much deeper than those attained in other experiments.

A valid substitute for CFC-11 (trichlorofluoromethane) for the production of rigid poly- urethane foams for thermal insulating materials, with blowing agents having low environmental impact, is not available yet. HCFC-141b and n-pentane, at present the most utilized physical blowing agents (PBAs), cannot definitely replace CFCs because of their environmental impact and flammability, re- spectively. The aim of the present work is to investigate the opportunity of employing HCOOH as a chemical blowing agent (CBA), other than water, which can in some applications replace physical blow- ing agents. Advantages and disadvantages have been highlighted after studying the isocyanate-formic acid reaction. Evidently, the introduction of new reactions into the polyurethane chemistry introduces a wide range of opportunities and challenges. # 1998 Elsevier Science Ltd. All rights reserved

The biodegradation of volatile fully chlorofluonnated hydro carbons (CFCs), partly chlorofluorinated hydrocarbons (H CFCs) and vinyl chloride (VC) were investigated in compost and marl in laboratory studies. Trichlorofluoromethane (R11), dichlorodifluoromethane (R12), 1,1,2-trichlorotriflu oroethane (R113), difluoromethane (R32) and VC were bio degradable in compost under anaerobic conditions, probably by methanogenic bacteria. The anaerobic decomposition products of R11 were dichlorofluoromethane (R21 ) and chlo rofluoromethane (R31). The degradation product of R12 was chlorodifluoromethane (R22). R11 and its degradation prod ucts have the inhibiting effects of the R12 degradation under anaerobic conditions. The partly halogenated hydrocarbon R22 and VC were degraded preferentially under aerobic con ditions in marl, probably by methanotrophic bacteria. Under aerobic conditions R22 and VC have inhibited the biodegra dation of methane by methanotrophic bacteria.

Although a number of hydrofluorocarbons (HFCs) and hydrochlorofluorocarbons (HCFCs) have been developed as possible substitutes for restricted chlorofluorocarbons (CFCs), it is not easy to satisfy both the industrial and environmental requirements. In the case of blowing agents, HFC 245fa and cyclopentane are presently expected to be promising alternatives to the traditional agent CFC 11 (trichlorofluoromethane). Gaseous thermal conductivities of six fluorinated methyl ethyl ethers, which are potential replacements for traditional blowing agents, have been measured by a transient hot-wire method. Temperature and pressure ranges of the measurements are from 303 K to 343 K and up to 0.4 MPa, respectively. The uncertainty of the thermal conductivities obtained is estimated to be within {+-}1%. Simple correlation equations were developed to represent the temperature and pressure dependences on the experimental thermal conductivities. Comparisons of the thermal conductivities between the present fluorinated ethers and those of traditional blowing agents CFC 11 (trichlorofluoromethane) and HCFC 141b (1,1-dichloro-1-fluoroethane) are given.

The pressure−density−temperature P(ρ,T) behavior of 18 liquids that are potential working fluids in thermal machinery has been measured using a vibrating tube densimeter. For each liquid, the data were taken on isotherms spaced at intervals of 5 K to 10 K spanning the temperature range 245 K to 370 K. The pressures ranged from just above the vapor pressure (or the critical pressure) to 6500 kPa. The results of measurements at more than 12 000 thermodynamic points are summarized by correlating functions. Comparison with data from other laboratories indicates that the relative expanded uncertainty in the measured densities is less than 0.05%, except in the critical region. The repeatability of the measured densities is on the order of 0.005%. For each liquid, the P(ρ,T) data were extrapolated to the vapor pressure to obtain the density of the liquid at the vapor pressure. The fluids studied (and their designations by the refrigeration industry) were trichlorofluoromethane (R11), chlorodifluoromethane (R22),...

The kinetics of trichlorofluoromethane (CCl3F) hydrate formation in water-in-oil emulsions stabilised by a non-ionic surfactant (Berol 26) were studied by means of dielectric spectroscopy. The dielectric spectra were recorded between 10 MHz and 1 GHz using time domain spectroscopy. A shell model of the dispersed droplets was used to determine the conversion of clathrate hydrate in the emulsion droplets. Simulations of the experimental findings are based on a simple reaction kinetics model. The model consists of three processes: the diffusion of CCl3F from the continuous oil phase into the dispersed water phase, the slow uncatalysed formation of clathrate hydrate, followed by an autocatalytic production of clathrate hydrate. The overall process is limited by the diffusion of CCl3F from the continuous oil phase into the dispersed water droplets.

The hydrogenolysis of carbon tetrachloride to chloroform, and of trichlorofluoromethane to hydrodichlorofluoromethane, are catalysed by the complexes RuCl 2 (PPh 3 ) 3 and RuCl 2 (dppe) 2 . The conversion of carbon tetrachloride into chloroform is more complete than the conversion of trichlorofluoromethane into hydrodichlorofluoromethane.

A Penning ion source for volatile organic compounds is described. Design, operating conditions, and properties of the ions generated are reported. The source operates at pressures ranging from 10−5 to 10−3 mbar; a sensitivity of 1.4 × 10−4 A/mbar is achieved. Mass spectra of 4-methyl-2-pentanone, ethyl benzoatc, dimethyl sulfoxide, trichlorofluoromethane and 1,1,2-trichlorotrifluoroethane obtained at low discharge currents are almost identical with their corresponding electron impact spectra at 70 eV. Two different discharge modes, depending on pressure, were found. The average energy of the ions is proportional to the potential of the ion source (〈E〉 = 0.64U, energy given in eV). Multiply charged Ar ions, Arn+, up to n = 4, have been observed.

Catalytic oxidation can be an effecitve and economic alternative to thermal oxidation for the destruction of halogenated hydrocarbons (HHC) which are known to deplete stratospheric ozone. Existing oxidation catalysts, noble metal and metal oxides are expensive and can deactivate when treating pollutants containing halogens. Current operation of thermal and catalytic processes require downstream gas scrubbing to remove acidic by-products HCl and Cl2 as well as corrosion resistant materials of construction. In response to the need for a better treatment process, a catalyst—sorbent that simultaneously destroys the HHCs and captures the halogens is being developed, and our initial results are presented in this paper. In this catalyst—sorbent, copper and manganese oxides are supported on sodium carbonate. The metal oxides are responsible for catalyzing the oxidation reactions and sodium carbonate captures the chlorine by forming NaCl and releasing carbon dioxide. Powder X-ray diffraction results show a significant conversion of the carbonate occurs as chlorine is captured. X-ray photoelectron spectroscopy has verified that the change between fresh and used catalyst also occurs near the surface. Trichloroethylene (TCE), trichlorofluoromethane and toluene are shown to be completely converted at a space velocity of 6700 h−1, temperatures 250°–400°C, and feed concentrations 30–350 ppm of pollutants in moist air. A chlorine balance shows that more than 98% of the chlorine from converted TCE remains in the catalyst—sorbent. Comparisons of this catalyst with others in the literature show it is a viable catalyst for the treatment of low concentrations of air pollutants.

Acetyl hypofluorite (AcOF) has been previously prepared using CFCl 3 (CFC-11) as a solvent. It was found that acetonitrile can replace trichlorofluoromethane without sacrificing the efficiency and the regio- and stereo-selectivity of the addition of AcOF to olefins. Most other solvents tested proved to be inadequate for the synthesis of AcOF, despite the fact that fluorine does react with the dispersed sodium acetate present in the solvent.

It was observed that the reaction of CFCl3 with thiophenoxide gave only 10% of the corresponding thioether. On the other hand, these thioethers could be prepared in excellent yield from diaryl disulfides and CFCl3 in the presence of sodium hydroxymethanesulfinate in aqueous DMF at 4 atm pressure of nitrogen. Dechlorination of the thioether (PhSCFCl2) with different reducing agents were studied. Most of the reducing agents eliminated both fluorine and chlorine functionalities or gave the hydrolyzed products. But its sulfone on treatment with Zinc in methanol gave monochlorofluoromethyl and fluoromethyl phenyl sulfone in good yields. Darzens reaction of these compounds was also studied.

Fluorinated derivatives of dimethyl ether may offer some solutions to the problem of finding fluids which have suitable properties to provide alternatives to CFCs. Using a method of estimation of thermodynamic properties, we present in this paper a modelling of the thermodynamic behaviour of three fluids within this class of compounds: the bis-difluoromethyl ether E134, the difluoromethyl fluoromethyl ether E143 and the difluoromethyl dichlorofluoromethyl ether E123b. These fluids are not very well known and can be used in compression heat pumps, as they are not toxic and they do not have an important effect on the ozone layer. Taking into account the concordance between physical characteristics and the cycle performances, E143, E123b and E134 can be considered as substitutes of R11 (trichlorofluoromethane), R113 (trichlorotrifluoroethane) and R114 (dichlorotetrafluoroethane), respectively.

The influence of solvents on micellar architectures of block copolymers composed of poly(1H,1H-dihydroperfluorooctyl methacrylate) and poly(ethylene oxide) was investigated. In this study, binary solvents with desired proportions were chosen, which had remarkable influence on the morphology of the resulting micelles. With simple adjusting the composition of the binary solvent of chloroform and trichlorofluoromethane, interesting shapes of micelle-like aggregates, such as core-shell, cylinder, worm-like and inverted micelles were formed with sizes of 15, 70, 30 and 250 nm, respectively. In the case of methanol/water system, core-shell spheres and vesicles were produced by varying the proportion of the contents. The morphologies were also tuned to honeycomb-like and bowl-shaped micelles as well as large planar lamellae with holes in DMF and water binary solvent.

The first cholroflurocarbon (CFC), CFC-12 (dichlorodifluoromethane, CCl2F2), was invented by Thomas Midgley, Jr. and Alfred Henne in 1928 by the fluorination reaction of carbon tetrachloride with antimony trifluoride, and immediately after it was identified as a best refrigerant in performance, CFC-12 was commercialized in 1930 in Du Pont Company as a nonflammable and nontoxic refrigerant to replace toxic refrigerants such as ammonia and sulfur dioxide in electric refrigerators (Giunta 2006). After the invention of CFC-12, other industrially important CFCs, CFC-11 (trichlorofluoromethane, CCl3F), and CFC-113 (trichlorotrifluoroethane, CCl2CClF2) were successively introduced into the market during 1930s–1940s.

Reverse micellization of nonionic surfactants in apolar media was applied to the formulation of solution phase, pressurized inhalation aerosols, employing soya lecithin (SPC) and water in chlorofluorocarbon (CFC) blends. The use of a 30/70 mixture of trichlorofluoromethane (Pll) and dichlorodifluoromethane (P12) resulted in the formation of stable, isotropic systems containing 0.5–2.0% (w/v) SPC and solubilized water; R (moles water/moles SPC), 0.9 to 4.28. In systems containing

Dichlorofluoromethane, trichlorofluoromethane and tetramethylsilane were used in the static coating of small diameter capillary columns (5 to 50 μm I.D.) in order to obtain highly efficient columns for gas and supercritical fluid chromatography. Capillary columns of 5-, 10-, 25-, and 50-μm I.D. were coated with stationary phase films of SE-33, SE-54, OV-215, 50% n-octyl, 45% phenoxypolyethyl ether, 50% liquid crystal, 25% biphenyl, 50% pentafluorophenyl and 50% cyanopropyl polysiloxane stationary phases. Resultant evaluations of these columns in gas chromatography gave approximately 9000, 66 000, 45 000, and 19 000 plates m−1, respectively, for the different internal diameters. Important parameters which affect coating efficiency are identified and discussed in detail.

Reductive addition of trichlorofluoromethane to ketones initiated by the Mg/LiCl system at −20 °C to −15 °C gave dichlorofluoromethyl carbinols in moderate yield.

Ethanol (95%) and glycerin were found to plasticize freeze-dried cubes of beef for reversible compression. Both are easily applied and plasticization appears to be rapid and effective. Appearance and texture of the reconstituted, compressed product compared favorably with that of noncompressed product and product plasticized by partial rehydration to 10% moisture; however, the glycerin and ethanol treatments gave a slight off-flavor. Vegetable oil and trichlorofluoromethane did not provide adequate plasticization. Polar liquids appear to be required for plasticization of dried beef for compression.

Adsorption isotherms for trichlorofluoromethane and carbon tetrachloride on a commercial silica gel are reported. All isotherms are type I and exhibit hysteresis. At relative pressures greater than the lower closure point of the hysteresis loop the adsorbates can be regarded as capillary liquids at negative pressure. The molar volumes of the capillary liquids are greater than those of the corresponding bulk liquids, and the dependence of molar volume on pressure is well represented by an equation of state proposed by R. J. Speedy (J. Phys. Chem. 80, 982, 1982). The compressibilities of the capillary liquids are greater than those of the corresponding bulk liquids.

A gas chromatographic method has been developed for the detection and identification of some volatile organic compounds in whole blood, plasma or serum. After incubation of the sample (200 microliters) together with the internal standard solution in a sealed vial, a portion of the headspace is analysed using a 2-m glass column packed with 0.3% (w/w) Carbowax 20M on Carbopack C, 80-100 mesh. The column oven, after a 2-min isothermal period, is programmed from 35 to 175 degrees C at 5 degrees/min and held for 8 min. The effluent is monitored by both flame-ionisation and electron-capture detection, and peak assignment is by means of retention time and relative detector response. The method has proved applicable to the detection of bromochlorodifluoromethane, n-butane, carbon tetrachloride, chlorobutanol, cryofluorane (Halon 114), dichlorodifluoromethane (Halon 12), ethyl acetate, halothane, isobutane, isopropanol, isopropyl nitrate, methyl ethyl ketone, propane, tetrachloroethylene, toluene, 1,1,1-trichloroethane, 2,2,2-trichloroethanol, trichloroethylene and trichlorofluoromethane (Halon 11) in blood specimens obtained from patients suspected of abusing these agents.

The levels of halocarbons have been determined in rural air in central Michigan using a sampling procedure employing pre-concentration on a porous polymer. The samples were analyzed by gas chromatography (GC) with an electron capture detector. Both qualitative and quantitative confirmation of the results were achieved by GC-mass spectrometry. Trichlorofluoromethane, chloroform, 1,1,1-trichloroethane, carbon tetrachloride, trichloroethylene and perchloroethylene were determined in the range of 30–130 parts per trillion. These concentrations agree well with data obtained by others in Washington state and Ireland indicating even distribution of the halocarbons in these latitudes.

Beer with an onion-like off-flavour is found to contain two unusual sulphur compounds: (1-methylethyl)-thiirane and 2-mercapto-3-methyl-1-butanol. The off-flavour is attributable to the latter, previously unknown compound. The methods used are: extraction of beer with trichlorofluoromethane, GC analyses of extractives and reference compounds, using a sulphur sensitive flame photometric detector, and GC-MS. Both of the new sulphur constituents are synthesized and their structures ascertained by NMR and MS.

Organic fluorine comounds are widely used for working fluid in industry. Applications and practical examples are described in regard of trichlorofluoromethane (F-11), 1, 2-dichlorotetrafluoroethane (F-114), 1, 1, 2 -trichlorotrifluoroethane (F-113), 2, 2, 2-trifluoroethanol (CF3CH2OH), bromotrifluoromethane (CF3Br), trifluoromethane (F-23) and dichlorodifluoromethane (F-12).

Treatment of commercially available uracil nucleotides and dinucleoside phosphates in methanolic solutions with trifluoromethyl hypofluorite in trichlorofluoromethane (Freon 11) gave adducts which were converted into the corresponding 5-fluorouracil nucleotides in basic solution. This procedure circumvents certain problems involved in phosphorylation of the rather inaccessible and expensive 5-fluorouracil nucleosides.Salts of both 5-fluorouridine-5′-monophosphate (5′-FUMP) and 5-fluorouridine-3′,5′-cyclic monophosphate (cFUMP) were crystallized and fully characterized. The procedure is not readily applicable to dinucleoside phosphates.

The halogenated aliphatic hydrocarbons represent one of the most important categories of industrial chemicals from a consideration of volume, use categories, environmental and toxicological considerations and hence most importantly, potential population risk. The major halocarbons reviewed, primarily in terms of their occurrence, utility, stability, distribution, and levels of exposure as well as their metabolism, carcinogenicity and mutagenicity included: vinylchloride, vinylidene chloride, trichloroethylene, perchloroethylene, ethylene dichloride, ethylene dibromide, chloroprene, chloroform, carbon tetrachloride, fluorocarbons (trichlorofluoromethane and dichlorodifluoromethane), epichlorohydrin, halohydrins (2-chloro- and 2-bromoethanol) and haloethers ( bis (chloromethyl); chloromethyl'-methyl; bis (2-chloroethyl)- and bis (2-chloroisopropyl)ether. In many instances, data were not available to assess world production, populations at risk and degrees of exposure. With the exception of vinylchloride, vinylidene chloride, epichlorohydrin and 2-halo ethanols, there is an acknowledged paucity of definitive mutagenicity data concerning the majority of halogenated hydrocarbons. Their ubiquitous distribution, and in a number of cases, their carcinogenicity both in man and animals, dictates the urgent need to more exhaustively investigate their potential mutagenicity.

Several anomalous features of the adsorption isotherms obtained with tetrachloroethylene and trichlorofluoromethane on anhydrous nickel sulfate at 20.0, 5.8, and −7.5 °C, have been explained using a parallel plate pore model. Application of the Kelvin equation to the system indicates that adsorption hysteresis is due primarily to contact angle hysteresis, and that the thickness of the adsorbed layer that does not participate in meniscus formation is independent of relative pressure. Heats of immersion calculated from the estimated contact angles, and from heats of adsorption, have provided some support for the model.

A specific and sensitive method is described for the determination of residual ethylene oxide, dichlorodifluoromethane and trichlorofluoromethane in sterilized plastic surgical equipment. Residues are isolated from the plastics by high vacuum distillation and analysed by gas chromatography using an exponential dilution apparatus, to avoid the use of solvents. Under the conditions specified, a lower limit of 1 ppm of each component could be detected in blood giving sets of which the main plastics material was PVC. The rate of loss of each component has been studied, to indicate the necessary holding time of the material before it can be considered safe to use.

A convenient method for the sampling and total analysis of the propellents and active agents contained in aerosol irritant projectors has been developed. A gas chromatograph equipped with a column packed with 6% Carbowax 20M on Chromosorb G and coupled to a mass spectrometer provides both quantitative and qualitative analysis for the components of a typical irritant projector. The main lachrymator, bromoacetone, represented 1.5% and the propellents dichlorodifluoromethane and trichlorofluoromethane, comprised 97.7% of the aerosol mixture.

Separating funnel extractions of ethanolic solutions of esters and alcohols using pentane showed preferential removal of esters. Trichlorofluoromethane was less selective and ether showed no selectivity at all. The amounts of both alcohols and esters extracted by an equal volume of pentane decreased with increase in ethanol concentration, this decrease being most marked for alcohols. Increase in the amounts of components extracted by a fixed volume of solvent would, however, generally be expected from concentrating ethanolic solutions. Similar extractions, using pentane showed continuous extractors generally to be more efficient. Recoveries, and the ability to extract esters selectively in the presence of alcohols, were dependent not only on the ethanol concentration but also on the degree of purification imposed on the recycling solvent. The selective nature of pentane was lost in the process of increasing efficiency.

The sulphonation of p-dichlorobenzene with sulphur trioxide has been studied in trichlorofluoromethane as solvent. The main products are (pyro)sulphonic acid and sulphonic anhydride. The formation of sulphone is very small. The sulphonation is of first order with respect to both substrate and sulphur trioxide, and proceeds without a primary kinetic isotope effect of hydrogen (kH/kD = 1·08 ± at −28°). The mole-ratio of consumed sulphur trioxide to converted p-dichlorobenzene is equal to 2. It is suggested that the sulphonation proceeds via 1-benzenonium-1-sulphonate and 1-benzenonium-1-pyrosulphonate as the subsequent reactive intermediates, the formation of the former intermediate being rate limiting. The dependence of the sulphonation products on reaction time indicates that the (pyro)sulphonic acid is the initial product and that the sulphonic anhydride is formed at a later stage. The experimental data accord with formation of the anhydride by reaction of the pyrosulphonic acid with 1-benzenonium-1-sulphonate. The kinetics of sulphone formation comply with a mechanism in which ArS3O9 is the effective sulphonylating entity.

NMR evidence is presented for complex formation between nitromethane and sulfur trioxide in thrichlorofluoromethane as solvent according to . In addition, kinetic evidence for complex formation between nitrobenzene and sulfur trioxide in trichlorofluoromethane was obtained from sulfonation studies of that system.

Liquid polyols consisting ofthreo-orerythro-9,10-dihydroxystearic acid previously reacted with 1, 2, 4, 6 and 8 moles of propylene oxide were adjusted with triisopropanolamine to equivalent weight 100. Using trichlorofluoromethane as blowing agent and triethylenediamine as catalyst, the adjusted polyols were foamed by reaction with a prepolymer made from oxypropylated sorbitol and tolylene diisocyanate.

The analysis of minor volatile constituents in alcoholic beverages presents difficulties because of the relatively high concentrations of a few higher alcohols. Volatile components were extracted from a freshly prepared Riesling white table wine using the solvent trichlorofluoromethane, and analysed by combined gas chromatography-mass spectrometry. The higher alcohols were then removed from the trichlorofluoromethane extracts by treatment with propylene glycol, and the remaining components, mainly esters, were concentrated further. The final concentrate, whose volume represented about 0·01% of that of the wine, was analysed again, and in all, over 40 components were identified. Some of the esters observed, including the mixed ester, 3-methylbutyl ethyl succinate, have not been reported previously.

CCl 4 , HCCl 3 et FCCl 3 donnent l'ion hydrogenocarbonate; C 6 H 5 CCl 3 donne un melange de C 6 H 5 C(O)OO − et C 6 H 5 C(O)O − ; CF 3 CCl 3 et OHCH 2 CCl 3 donnent les anions carboxylates correspondants RC(O)O − ; et p,p'-DDT donne son produit de dechlorhydratation qui reagit avec O 2 − pour donner (p-ClC 6 H 4 ) 2 C=O

The initial rate of bromination of carbon tetrachloride is independent of surface-to-volume ratio and can be fitted to a rate law which assumes that the rate-determining step is Br + CCl4 → BrCl + CCl3; however, the overall temperature coefficient of the rate is inconsistent with the known thermochemistry of the system. The same anomaly has been reported recently in the fluorination of trichlorofluoromethane by Foon and Tait, and similar inconsistencies occur in the fluorination of carbon tetrachloride and the chlorination of bromotrichloromethane.

Exposure of dilute solutions of various dialkyl and cyclic N-chloro amines in trichlorofluoromethane to 60Co γ-rays at 77K gave the corresponding cations, R2ṄCl+, characterised by 14N, 35Cl, and 1H hyperfine coupling. The results suggest that these radicals are essentially planar at nitrogen, the SOMO being the N–Cl π* orbital. Similar treatment of dilute solutions in methanol or methyltetrahydrofuran gave the corresponding amino radicals, R2N˙, also characterised by their e.s.r. spectra. There was no evidence for the formation of the parent radical anions. These results are contrasted with those for N-halogeno imides and with the formation of σ* radicals from the cations R3N˙+ and halide ions.

Reaction of 1,2-dihydrobenzocyclobutene (DHBCB) with sulphur trioxide addition complexes leads to the formation of DHBCB-3- and DHBCB-4-sulphonic acid and the sultone of 2-(o-sulphophenyl)ethanol. The ipso : 3- : 4-substitution ratio is (25 ± 5) : (5 ± 3) : (70 ± 4) for CH3NO2–SO3 in nitromethane at 0° and (32 ± 6) : (7 ± 4) : (61 ± 5) for dioxan–SO3 in trichlorofluoromethane at 0–20°. DHBCB on reaction with concentrated sulphuric acid is mainly converted (ca. 90%) into polyxylylene. At 90% H2SO4 the terminal group is the 4-DHBCB system; below 90% H2SO4 it is in part replaced by the 2-(p-phenylene)ethyl sulphate group. The ethylene bridges in the polymers have mainly the meta-orientation. In addition the sulphuric acid soluble 2-(p-sulphophenyl)ethyl sulphate (3) and 5-[β-(p-sulphophenyl)ethyl]DHBCB-4-sulphonic acid (4) are formed. The ratio of (3) to (4) decreases strongly with increasing sulphuric acid concentration. Mechanisms for the formation of the polymers and (3) and (4) are proposed.

Isomer distributions for the sulphonation of 1,2,3- and 1,2,4-trimethylbenzene with concentrated aqueous sulphuric acid at 25.0° have been determined. The results are discussed in terms of sulphonation by H3SO4+ and H2S2O7 as sulphonating entities. The isomer distributions for the H2S2O7 mechanism are 90 ± 1% 4- and 10 ± 1% 5- substitution for the 1,2,3-isomer and 75 ± 2% 5- and 25 ± 2% 6-substitution for the 1,2,4-isomer, those for the H3SO4+ mechanism are 86 ± 1% 4- and 14 ± 1% 5-substitution with the former isomer andd 89 ± 2% 5- and 11 ± 2% 6-substitution by the latter. The deviations of the observed isomer distributions and of the partial rate factors for the H3SO4+ mechanism from those calculated on the basis of the additivity principle are discussed. The sulphonation of 1,3,5-trimethylbenzene with sulphur trioxide proceeds without a primary hydrogen kinetic isotope effect, kH/kD being 1.15 ± 0.13 and 0.98 ± 0.09 for nitromethane at 0° and trichlorofluoromethane at –35° respectively.