The title copyrolysis reaction at 600--700°C in the presence of steam or nitrogen as diluents has been investigated. The reactions were carried out by a flow method under atmospheric pressure using spheric quartz reactor. The range of molar ratio of bromotrifluoromethane to ethene in the feed gas was 0.14/1∼7/1, and that of the diluents concentration was 50∼95%. The range of the total space velocity was 900∼15000 h^-1. The conversions of bromotrifluoromethane in the reaction conditions were 1∼35%. The major products containing fluorine or bromine were 3, 3, 3-trifluoropropene, 1, 1, 1-trifluoropropane, trifluoromethane and hydrogen bromide. The minor products were bromoethene and bromoethane. Primary products of the reaction were 3, 3, 3-trifluoropropene and hydrogen bromide. The reaction rates at the diluents concentrations below 90% were first and zero order with repsected to bromotrifluoromethane and ethene, respectively. The conversions increased with an increase of the dilution over ca.90%. Effects of steam and nitrogen on the rates and products were almost equal. Formation mechanisms of these products were discussed.

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Aqueous solutions of proteins, such as bovine serum albumin, bovine fibrinogen, bovine γ-globulin, and human plasma fibronectin, were found to become turbid when flowed using a peristaltic pump through a polyethylene tube with an inner diameter of 2.0 mm. It seems likely that the turbid solution was formed as a result of denaturation and aggregation of protein molecules by the shear stress, because the turbidity was remarkably increased with the increasing shear rate.
No difference w as observed in the circular dichroism of proteins before and after flowing. This result is probably due to the evidence that the number of denatured and aggregated protein molecules is very small compared with that of the protein molecules in the whole solution. This evidence was confirmed by a GPC measurement of the protein solution after flowing.

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The reaction of isocyanuric acid with phenyl glycidyl ether was investigated as a model reaction of isocyanuric acid with epoxide resin. Isocyanuric acid is a kind of 1, 3, 5-triazine compound which is synthesized from urea. Isocyanuric acid (0.01 mol) was allowed to react with phenyl glycidyl ether (0.03 mol) in the presence of 2-methylimidazole (0.001 mol) at 160∼180°C for 1 h of stirring.
After being cooled, the reaction mixture was extracted with acetone, which was evaporated to give a residue.
The resid ue was then washed with dil. HC1 under reflux for 10 min in order to remove both unreacted 2-methylimidazole and the supposed basic adducts between 2-methylimidazole and phenyl glycidyl ether. Recrystallization of the dil. HCl-insoluble substance from methanol and successively from acetone gave a colorless crystalline compound.
The structure of this compound was determined to be 5-phenox ymethyl-2-oxazolidinone [2] by means of infrared, nuclear magnetic resonance and mass spectra. Alkaline hydrolysis of [2] gave an 2-aminoethanol derivative [3] supporting the estimated structure. A possib le reaction pathway for [2] is discussed.

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The intermolecular compound of isocyanuric acid and imidazole is very useful as a curing agent for epoxide resin.
The purpose of th is paper is to clarify the reaction of epoxide with isocyanuric acid contained in the intermolecular compound through the curing process of the epoxide resin compound. The intermolecular compound (0.01 mol) and phenyl glycidyl ether (0.05 mol) were heated and stirred at 160∼180°C for 1 h. After being cooled, the reaction mixture was extracted with acetone, which was evaporated to give a residue. The residue was then washed with dil. HCl under reflux for 10 min in order to remove the basic compounds.
Thus, the residue left a dil. HCl-insoluble substance, which ga ve a colorless crystalline compound by washing with water and recrystallization from methanol. The structure of the crystalline compound was determined to be 3-(2-hydroxy-3-phenoxypropyl)-5-phenoxymethyl2-oxazolidinone [2] by means of infrared, nuclear magnetic resonance and mass spectra.
Then, 10 g of the intermolecular compound was added to 100 g of Epikote #828, and the mixture was heated at 150°C for 1 h to give a cured resin, which was ground in to powder.
After being washed with hot water using a Soxhlet extractor in order to remove un reacted isocyanuric acid, the dried powder was examined by infrared spectroscopy. The infrared spectrum of the powder is not only different from that of isocyanuric acid, but also shows new peaks suggesting the existence of isocyanurate and 2-oxazolidinone rings at 1690 and 1740 cm-1, respectively.

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Cured epoxide resins were obtained by various curing conditions and an equivalent ratio of epoxide resin and isocyanuric acid in the presence of imidazole compound.
The glass transition temperature and the electrical and mechan ical properties of the cured resins obtained were measured using a free decrement oscillation method, an electrometer and a tensile and flexual tester. The glass transition temperature of the cured resins depends on the curing conditions and the equivalent ratio of isocyanuric acid and epoxide resin. The infrared spectra of the cured resins show the existence of isocyanurate and 2-oxazolidinone rings in their chemical structure. The ratio of isocyanurate and 2-oxazolidinone rings depends on the curing conditions for the compounds rather than the equivalent ratio of isocyanuric acid and epoxide resin. The glass transition temperature of the cured resin having isocyanurate rings was higher than that of the cured resin having 2-oxazolidinone rings. The volume resistivity, bending strength, and modulus and shear strength of the cured resins were superior to those of epoxide resin polymerized with 2, 4-diamino-6-[2-(2-methyl-1imidazoly)pethyl]-1, 3, 5-triazine under the same curing conditions.

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A simplified method is presented for predicting the breakthrough time of two or three component organic solvent vapors on an activated carbon fixed hed. The breakthrough did not be gin simultaniously for each component, and the maximum value of the outlet vaopr concentration for the first breakthrough component became higher than the inlet vapor coneentration. The shape of the breAthrough curves depend on many factors, such as, kinds, vapor concentration and the mixing ratio of solvent vapors. As a typical example, breakthrough appeared at quite different times for the ethyl acetate-1-butanol system and at about the same time for the benzene-hexane system. The higher vapor pressure component tended, with a few exceptions, to break earlier than the lower one. This tendency was independent of the vapor concetration or the mixing ratio. The breakthrough time for the first component became the harmonic mean value of each pure component.

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Bis[1-(4-dimethylaminophenyl)-2-phenylethanedithione]nickel(0) (BDN), a Q-switch dye for neodymium lasers, was bleached in the presence of piperidine or N, N-dimethylformamide (DMF). The peak in the optical absorption spectrum of BDN shifted from 1100 nm to 1000 nm with progress of time. This bleaching may be due to reduction of BDN with DMF. After a few weeks, nikel was isolated from the solution BDN. α-Tocopherol accelerated the bleaching rate of BDN in DMF. Presumadly α-tocopherol reduces BDN more efficiently than DMF.

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Homogeneous chemical equilibria and electrochemical behaviors of three bis(β-diketonato)cobalt(II) complexes, viz., [Co(hfac)₂], [Co(tfac)₂] and [Co(acac)₂], in di methyl sulfoxide (DNISO) were studied by means of the conductivity flicl electronic spectral measur ements, poktrography, and cyclic voltaminctry with a platinum electrode; where hfac tfac- and acacrepresent the enolate anions of hexafluoroacetylacetone, trifluoroacetylacetone and acetylacetone, respectively. Tetrabutylammonium Perchlorate (TBAP) of 0.05 mol⋅dm-3 in the concentration was used as the supporting electrolyte fur voltammetric measurements. It was found that these complexes were involved in the following chemical equilibria in the solution:
In DC polarography, the first wave of [Co(hfac)₂] was presumed to be due to the two-electron reduction of CO²⁺, [Co(hfac)]⁺ and [Co(hfac)₂], and the wave of [Co(acac)₂] to that of monomeric and polymeric bis-comlexes. Furthermore, two waves of [Co(tfac)₂] corresponded to the two-electron reduction of [Co(tfac)]⁺ and [Co(tfac)₂], respectively; where the first wave included the kinetic current due to the preceding reaction.

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2'-Hydroxychalcones ([1a]∼[1g]) gave corresponding flavones ([2a]∼[2g]) by reaction with sulfur in boiling N, N-Dimethylformamide(DNIF), in comparatively short time and high yield.
In this reaction the anionic species may participate, and flavones would be formed directly from chalcones but not via the corresponding flavanones.

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The AlCl₃-catalyzed Fries rearrangement of phenyl phenylacetate [1] in chlorobenzene proceeded more rapidly with the higher ortho-para ratio than TiCl₄-catalyzed one (Table 1). In the Fries rearrangement of [1] in three solvents (chlorobenzene, toluene and nitrobenzene), the highest yield was given in nitrobenzene, but the order of ortho-para ratio was as follows: chlorobenzene>toluene>nitrobenzene (Table 1).2- and 4- Tolyl benzyl ketones were formed in the AlCl₃-catalyzed Fries rearrangement of [1] in toluene.
The ortho-para ratio in the Fries rearrangement of [1] without solvent increased rapidly at 50°C compared to that at 40°C. In the Fries rearrangement of [1], phenyl benzoate [4] and phenyl acetate 5 without solvent, the highest yield and ortho-para ratio were observed in the case of [1] (Table 3).

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Color development characteristics of diazonium thermo-sensitive systems were investigated using phase diagrams of coupler and thermo-sensitizer systems. Benzil, Phenyl-1-hydroxy-2naphthoate, and Benzoin were used as the thermo-sensitizer. Density versus temperature curves were characterized by three factors: color initiation temperature (T_in), color development temperature (T_cd), and tangent of the color development curve (γ). The γ was largest at the eutectic composition since the amount of molten coupler increases as the composition approaches the eutectic point. The T_cd and T_in were dependent on the eutedtic temperature.

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A highly accurate and simple method to determine the solubility of liquid organic compounds in water has been developed.
The TOC (Total organic carbon) method has revealed that the concentrations of alcohols and benzene in water can be accurately determined of removal procedure of IC (Inorganic carbon) is eliminated, as shown in Table 1.
Saturated aqueous solutions of organic co mpounds were obtained as follows: After shaking of a supersaturated aqueous solution, the mixture was allowed to stand until equilibrium was reached. Then an oil drop suspending in the mixture was broken by filtration of the mixture through a glass fiber filter paper (Table 2) moistened with water.

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The reactions of 2, 2, 2-trichloro-5-trifluoromethyl-2, 2, 2, 3-tetrahydro-1, 3, 4, 2-oxadiazaphospholes with various nucleophiles gave the novel tetrahydrooxadiazaphosphole derivatives bearing the corresponding substituents at 2-position. The reactions with 0-nucleophiles such as TMS-p-cresol afforded the 2, 2, 2-trisubstituted tetrahydrooxadiazaphospholes and, in contrast, that with N-methylaniline gave a 2, 2-disubstituted 2-chlorotetrahydrooxadiazaphosphole, and with p-anisidine, a phosphazene of tetrahydrooxadiazaphosphole was obtained. On the other hand, the trichlorotetrahydrooxadiazaphosphole was allowed to react with N'-phenyltrifluoroacetohydrazide, giving the novel spiro compound of two tetrahydrooxadiazaphosphole rings bearing phosphorus as a spiro atom. The steric configurations of thus obtained tetrahydrooxadiazaphospholes were investigated on the basis of the chemical shifts in ³¹P-NMR. Other spectral interpretations were also discussed.

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Both enantiomers of alkyl hydrogen 2-alkyl-2-fluoromalonates, which can be used for preparing fluorine-containing chiral compounds having potentially biological activity, were prepared in a practical scale by microbial methods. Thus, asymmetric hydrolysis of diethyl 2methy1-2-fluoromalonate with lipase gave the S-enantiomer, and with cellulase gave the Renantiomer.

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[2-(Trifluoromethyl)allyl]trimethylsilane [2] and [2-(trifluoromethyl)-1-(t-butoxycarbonyl)vinyl]trimethylsilane [4] were prepared in high yields from ethyl trifluoroacetate, which is one of the cheapest starting materials containing a trifluoromethyl group, and trifluoroacetaldehyde, which is easily derived from ethyl trifluoroacetate in two steps, respectively. These compounds [2] and [4] were allowed to react with electrophiles in the presence of catalytic amount of fluoride ion to give adducts in good to excellent yield, although the reaction did not take place under Lewis acidic conditions. However, the reaction of [2] with benzaldehyde dimethyl acetal, which is known to have high reactivity toward nucleophiles in the presence of Lewis acid, was proceeded by titanium(IV) chloride to give chlorinated adduct [10] in excellent yield, while using trimethylsilyl trifluoromethanesulfonate, desired compound [11] was given only in low yield. Since compound [4] was α, β-unsaturated ester, Michael addition with various nucleophiles also tried and gave good yields as well as high diastereoselectivity.

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Bis(hexafluoroisopropoxy)triphenylphosphorane[1] was prepared by the reaction of triphenylphosphine clibromide with hexafluoroisopropoxide in ether-dichloromethane solvent. The structure of [1] was determined by ¹³P-NMR, ¹⁹F-NMR and ¹H-NMR spectrum.
Phosphorane [1] which was prepared in situ readily reacted with alcohols at room temperature to form alkyl hexafluoroisopropyl ethers and/or olefins. Similarly, the reaction of [1] with carboxylic acids proceeded to form hexafluoroisopropyl esters in good yields.
Furthermore, while bis(2, 2, 2-trifluoroethoxy)triphenylphosphorane was i nert to N-nucleophile such as amines, [1] readily reacted with anilines to produce the corresponding Nhexafluoroisopropylated derivatives. Resulting N-(hexafluoroisopropyl)anilines were dehydrofluorinated by triethylamine to form 2-aryl-1, 1, 3, 3, 3-pentafluoropropenes. When anilines with ortho functional group such as -NH₂, -OH, -SH were used in this system, trifluoromethylated heterocyclic compounds were obtained via the addition-elimination process.

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A variety of trifluoromethyl compounds were synthesized by using FITS-2 or -3 i as pentafluoroethylating or heptafluoroisopropylating agent through the activation of the fluorine atoms situated ata-position. γ-Fluoro-γ-trifluoromethyl-substituted α, γ-unsaturated compounds [3], resulted from the reaction of FITS-2 with enol silyl ethers followed by dehydrofluorination, were shown to be useful intermediates for the synthesis of trifluoromethyl compounds. On the other hand, 4-pentafluoroethyl-2, 6-di-t-butylphenol was treated with a base to give 7-fluoro-7-trifluoromethylquinonemethide derivative [20], which was proved to be a key compound for the synthesis of aromatic compounds possessing a trifluoromethyl group at benzylic position. Similar use of FITS-3 i afforded useful synthetic methods for bis(trifluoromethyl)compounds.

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Tetrachloroisophthalonitrile was fluorinated into tetrafluoroisophthalonitrile with spray-dried potassium fluoride and sulfolane. Under the optimum conditions, i. e., for 5 h at 290°, the yield of tetrafluoroisophthalonitrile was ca.80%.
This polyfluorinated isophthalonitrile reacted with such nucleophiles as alcohols, phenols, and amines into the corresponding 4-substituted 2, 5, 6-trifluoroisophthalonitriles in excellent yields.
As a result of biocidal evaluation, it was found that these compounds possessed strong antimicrobial activities.

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The reaction of hexafluoropropene and dialkylamines to give mixtures of α, α-difluoroalkylamines and/or α-fluoro enamines, i. e.HFP-R₂NH was investigated by us. These adducts could be used as excellent fluorinating reagents for alcohols and carboxylic acids. These reagents were found to be superior to the known“Yarovenko reagent”which was formed via the reaction of chlorotrifluoroethene and diethylamine, owing to their readier preparation and higher stability.
Further, N²-aryl(or alkyl)-2, 3, 3, 3-tetrafluoropropionamidines were prepared by the reaction HFP-R₂NH reagents with aryl(or alkyl)amines.
Ortho-bifunctional benzenes such as 2-aminophenols, o-phenylenediamine, 2-aminothiophenol, and 2-aminobenzamide also reacted very easily with HFP-Et₂NH reagent, affording 2(1, 2, 2, 2-tetrafluoroethyl)benzoxazoles, -benzimidazoles, -benzothiazole, and 2-(1, 2, 2, 2-tetrafluoroethyl)4(3H)-quinazolinone respectively.
Moreover, HFP-R₂NH reagents were allowed to react with ureas into the N', N'-dialkyl-N²-carbamoy1-2, 3, 3, 3-tetrafluoropropionamidines, which were cyclized to give 6-alkoxy-lalky15-fluorocytosines with alkoxides.

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The compounds carrying an active fluoromethylene group such as α-fluoro-β-keto esters and β-diesters are recognized as useful intermediates for the synthesis of monofluoro compounds which are of great interest from the biological point of view. These building blocks were readily prepared from commercially available trifluoroethene or hexafluoropropene.
The monofluoro heterocycles synthesized from these building blocks include pyrazoles, coomarins, pyrimidines and benzodiazepines etc.
α-Fluoro-β-keto esters derived from trif luoroethene or hexafluoropropene as described above, were potent intermediates for monofluoro heterocycles.
As an example of those, 3-alkyl(or aryl)- 4-fluoro-5-hydroxypyrazoles were prepared by the reaction with hydrazines. The reaction proceeded in refluxing ethanol smoothly, and 4-fluorophrazoles were obtained in good yields.

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The LiAlH₄ reduction of 2-acetoxy-3-alkyl-1, 1-difluorocyclopropanes [2] in ether gave the corresponding β-fluoroallyl alcohols[3] with high stereoselectivity. The degree of the stereoselectivity was found to be affected by steric bulkiness of the alkyl substituent in the cyclopropanes. The selectivity may involve a sterically favourable ring-opening reaction in which the alkyl substituent rotates in an opposite direction toward the cyclopropane plane followed by elimination of fluoride ion through the inversion-like mode.
A stereospecific synthesis of conjugated fluoro diene[10] from 1, 1-difluoro-2-alkyl-3-(methoxycarbonyl methyl)cyclopropane[4a] the nitrile derivatives [4b], [4c] and the phenylsulfonyl derivatives[4d] was achieved by forming the a-carbanion which underwent the ring-opening reaction. (E, E)-Fluoro diene was obtained from trans-cyclopropane and ( E, Z)-fluoro diene from cis-isomer, preferentially.

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A synthetic method of 5-fluorouracil by a two-stage route has been developed; that is, the direct fluorination of orotic acid and the subsequent decarboxylation of the resulting 5-fluoroorotic acid. Solvent has an important role in the direct fluorination. Among the polar solvents suitable for the fluorination of orotic acid, the best one was formic acid containing 7∼15 wt% of water. Orotic acid reacted with elemental fluorine in the formic acid solvent at 0∼10°C to give 5-fluoro-6-hydroxy-5, 6-dihydroorotic acid which was readily transformed int o 5-fluoroorotic acid by heating in more than 70% yield.5-Fluoroorotic acid was decarboxylated in water under 5∼7 atm. at 150∼170°C to give 5-fluorouracil in a 90% yield.

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Reaction of diols, glycerol mono- and dihalohydrins with N, N-diethyl-1, 1, 2, 3, 3, 3-hexafluoropropylamine (PPDA) gave a propyl ester or a cyclic adduct as the major product. Thus, 2, 3-dibromopropyl-2, 3, 3, 3-tetrafluoropropionate was isolated in 52 yield from the reaction of 2, 3-dibromo-l-propanol with PPDA.
2-Diethylamino-2-(1, 2, 2, 2-tetraf luoroethyl)-1, 3-dioxane was obtained in 53 % yield from 1, 3-propanediol and PPDA.

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Chiral amides, Nvhich are potentially biologically active, were prepared from both enantiousers of ethyl hydrogen 2 -alkyl-2-fluoro-malonatc. From the point of view of the moleculare design of fluorine-containing compounds having the biological activity, chiral N-(2-fluoro-3mercapto-2-methylpropionyl)proline was also prepared.

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1-Fluoroanthraquinone was prepared from 1-nitroanthraquinone in ca.35% yield by fluorodenitration.1-Hydroxyanthraquinone was also obtained on this reaction as a secondary product.
In the presence of tetrafluorophthalonitrile, 2, 4-dinitrofluorobenzene or 2, 4-dinitrochlorobenzene, 1-nitroanthraquinone gave 1-fluoroanthraquinone in ca.70% yield without formation of 1-hydroxyanthraquinone.
Fluorodenitration of 2-nitroanthraquinone also was investigated.

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The title enol silyl ether [3] was readily prepared from 3, 3, 3-trifluoropropiophenone with trimethylsilyl triflate, and its reactions with a variety of carbon-electrophiles were studied. The silyl ether [3] was found to react with benzaldehyde acetal, benzaldehyde, and chloromethyl ethyl ether, whereas [3] did not undergo the expected C-C bond formation with aliphatic acetal, aliphatic aldehyde, and acyl chloride.
The unique reactivity of [3] was compare d with those of the non-fluorinated counterpart and the enol silyl ether of methyl 3, 3, 3-trifluoropropionate.

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N-Trifluoromethyl-N-nitrosobenzenesulfonamide and its derivatives bearing electron-donating or electron-withdrawing groups on the benzene rings were synthesized by the reaction of trifluoronitrosomethane with hydroxylamine at low temperature, followed by treatment with a base in the presence of arenesulfonyl halides. N-Trifluoromethyl-N-nitrosomethanesulfonamide was also synthesized.
On the other hand, the use of acid halides or acid anhydrides, haloformates, and carbamoyl halides instead of the sulfonyl halides afforded N-trifluoromethyl-N-nitroso-amide, -carbamate, and -urea derivatives, respectively.

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New fluorinated dicarboxylic acids, 3, 3, 4, 4, 5, 5, 6, 6-octafluorooctanedioic acid [2 a] and 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8-dodecafluorodecanedioic acid [2 b], having a methylene group between perfluoroalkylene and each carboxyl group, were synthesized in high yields, by the oxidation of corresponding diols[1] with CrO₃/H₂SO₄ (Jones reagent). Oxidation of [1] with other oxdizing reagents such as nitric acid and KMnO₄ did not virtually give[2].
These dicarboxylic acids are useful not only as monomers of fluorinated polycondensation polymers, but also as precursors of other difunctional monomers such as bis(carboxyl chlorides)[3]and diisocyanates [4].

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N-Phenyltrifluoroacetimidoyl chloride reacted with isoquinoline and trimethylsilyl cyanide in the presence of a catalytic amount of aluminium chloride to give a Reissert analogue bearing trifluoromethyl group, which was then cyclized by treatment with fluoroboric acid, resulting in the formation of 1-amino-2-phenyl-3-trifluoromethy1-2 H-imidazo[4, 3-a]isoquinolinium tetrafluoroborate. The tetrafluoroborate was next treated with trifluoroacetic anhydride to give the trifluoroacetamide derivative, which was converted to the corresponding mesoionic compound in the presence of sodium hydrogencarbonate.

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Reactions of α, ω-diiodoperfluoroalkanes with sulfur trioxide or oleum produce highly unique compounds.1, 2-Diiodotetrafluoroethane was reacted with sulfur trioxide to give an intermediate sulfate which was easily decomposed by potassium fluoride to produce difluoroiodoacetyl fluoride. The acetyl fluoride, having two adjacent reactive sites, an ICF₂- and a -COF, was expected to have a high reactivity.
It was reacted with metal p owders of copper and silver. The reactions produced not only the coupled perfluorosuccinyl difluoride, but also gave perfluoro-3-oxa-4-pentenoyl fluoride, a product formed by the participation of both reactive sites. The mechanism of the reaction was also discussed.

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