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Cytidine, uridine, and thymidine are transformed into the ring-contracted 1-substituted derivatives by ozone. A plausible mechanism is proposed.

Trifluoroacetaldehyde ethyl hemiacetal 1 readily reacts with various enamines 2 in hexane at room temperature for 1 h to give the corresponding β-hydroxy-β-trifluoromethyl ketones in good yields.

The treatment of α-alkoxycarbonyl-α,β-unsaturated trifluoromethyl ketones (1) with β-aminocrotonates (2) affords 2-hydroxy-6-methyl-2-trifluoromethyl-1,2,3,4-tetrahydropyridines (3), which undergo facile dehydration by use of phosphorus oxychloride / pyridine adsorbed on silica gel, giving good to high yields of 1,4-dihydro-2-methyl-6-trifluoromethylpyridines (4).

2,3,3-Trifluoro-1-aryl- or -1-alkyl-prop-1-enyl toluene-p-sulfonates 1, readily available from 2,2,3,3-tetrafluoropropanol, react smoothly with alcohols in the presence of sodium hydroxide at ambient temperature for 1 h to afford the corresponding α-fluoro-β,β-dialkoxy ketones 2 in good to excellent yields.

The reaction of (Z)- and (E)-6,6,6-trifluoro-4-trifluoromethyl-4-hexen-3-ones (1) with diazomethane afforded the corresponding cis- and trans-pyrazolines (2), respectively. Photochemical and thermal decompositions of the r-3, t-4-bis(trifluoromethyl)pyrazoline gave selectively r-1, t-2-bis(trifluoromethyl)-1-propionylcyclopropane (3) and 3,4-bis(trifluoromethyl)-2-ethyl-4,5-dihydrofuran (4). On the other hand, those transformations of the r-3,c-4-isomer of the pyrazoline gave a mixture of the r-1,c-2-isomer of 3, 4, and 4,5-bis(trifluoromethyl)-5-hexen-3-one (5).

Cytidine, uridine, and thymidine are transformed into the ring-contracted 1-substituted derivatives by ozone. A plausible mechanism is proposed.

α-Alkoxycarbonyl-α,β-unsaturated trifluoromethyl ketones are easily prepared by Knoevenagel condensation of aldehydes with trifluoroacetoacetates in the presence of silica gel functionalized with amino groups and p-toluenesulfonic acid. The method gives the products in moderate to good yields.

N-(Nitrofluorenylidene)anilines were synthesized by the condensation of nitrofluorenones with substituted anilines in the presence of zinc chloride. 2-Methyl, 2-ethyl, 2-isopropyl and 2-trifluoromethyl derivatives from 2,4,7-trinitrofluorenone showed high compatibility to polycarbonate and good properties as electron transport materials in positive charge electrophotography. The 2-isopropyl and 2-trifluoromethyl derivatives were substantially stable for the repetition test. N-(2,4,7-Trinitro-fluorenylidene)-2-isopropylaniline was negative for the Ames test.

The reaction of coumarins 1 with bis(perfluoroalkanoyl) peroxide gave selectively 3-perfluoroalkylcoumarins 2 in moderate yields (eqn. 1). The emission maxima (λ em ) of 2 were observed around 460 nm (R 1 = CH 3 , R 2 = (CH 3 CH 2 ) 2 N), and 550 nm (R 1 = CF 3 , R 2 = (CH 3 CH 2 ) 2 N), showing bathochromic shifts (20, 50 nm) compared with 1 , respectively. Relative fluorescence intensity (RFL) of 2 was lower than 1 . The light stability of 2 was much better than 1 . No remarkable differences among CF 3 , C 3 F 7 and C 7 F 15 groups for λ max , λ em and RFL were observed. The perfluoroalkylation of azobenzenes and anthraquinones also afforded the perfluoroalkyl derivatives ( 3–6 ).

In recent years, the ozone treatments of waste water has attracted attention because of its extensive uses. In this report, the conditions of decoloring reaction by ozone, mainly for a watersoluble azo dye, C. I. Acid Orange 12 (A. O. 12), have been reported. The results obtained are as follows:1) In the decoloring of A. O. 12 by ozonea) The reaction is of pseudo first order.b) The dissociation of OH group of the dye and the self-decomposition of ozone appear to accelerate the reaction.c) The aromatic rings are cloven to form carboxylic acids.2) Ozone mainly attacks N=N bond in mono azo dyes.3) A. O. 12 is considered to decompose to the final products via intermediates containing active oxygen.

Ozonization of azobenzenes in chlorinated solvents gave 2-chloroazobenzene, 4-chloroazobenzene, azoxybenzene, glyoxal and hygroscopic compounds, whilst similar reaction of phenylazonaphthalenes and azonaphthalenes gave only limited formation of azoxy derivatives. The reaction of a series of azobenzenes with ozone to give azoxybenzenes was investigated with particular respect to substituent and solvent effects.

Substituent effect on the ozonation of anthraquinones was discussed. Reactivity of anthraquinones with ozone increased as greater was the electron donative property of the substituent. When the unsymmetrical anthraquinones were ozonized, the remarkable selectivity of ozone attack on the both aromatic rings was observed.

The ozonolysis of 1-phenylazo-2-naphthol was studied using ozone in an oxygen stream. 1-Phenylazo-2-naphthol reacts with ozone to give benzene, chlorobenzene, phenol, o-naphthoquinone, phthalide and phthalic anhydride. The mechanism of the reaction is explained as an electrophilic attack of ozone with the hydrazone tautomer of 1-phenylazo-2-naphthol.

Decolorization reactions of hydroxyazo dyes are examined using mainly 4–phenylazo–1–naphthol as the model. Based on the fact that the reaction products are phenol, 1 4–naphthoquinone and nitrogen gas, the reaction mechanism is discussed. In the first step of the reaction, ozone attacks the hydrazo group in 4–phenylazo–1–naphthol and the reaction proceeds via the “ene” mechanism.

When phenothiazine and phenoxazine were ozonized in dichloromethane, the cation radicals and the ozonate anion radical were detected, whereas, in the ozonization of phenoxathiin and thianthrene, these radicals were not observed. Formation of these radicals was more favorable as greater was the polarity of the solvent and lower was the oxidation potential of the substrate. Ozonization of phenothiazine and phenoxazine in polar solvents was explained by the electron-transfer mechanism accompanied by the electrophilic ozone attack, and that of phenoxathiin and thianthrene by the electrophilic ozone attack alone.

The reactions of phenolphthalein, which exists as a lactone-quinonoid tautomeric mixture in solution, and aurin with ozone have been examined. The reactivity of the lactone tautomer of phenolphthalein with ozone was found to be low and the ozone attacks the aromatic ring. In the case of the quinonoid tautomer the ozone readily reacts with the carbon skeleton. In the case of aurin ozone also attacks the carbon skeleton.

The reaction of Malachite Green (MG, 1a), a model compound of triphenylmethane dye, with ozone proceeded via two paths. The first path involved an ozone attack at the dimethylamino moiety to give a N-formylmethylamino derivative 4a. The second path produced 4-(dimethylamino)benzophenone (2a) and p-(dimethylamino)phenol (6). Other ozonized products, 3a and 5a were also detected. The following is a discussion of the ozonization mechanism.

The interaction between water-soluble basic vinyl copolymer and acid dyes was studied by the methods of spectrophotometry and dialysis equilibrium.A copolymer of 2-vinylpyridine and 1-vinyl-2-pyrrolidone (I) was chosen as a water-soluble basic vinyl copolymer. As acid dyes were used C. I. Acid Orange 7 (II a), C. I. Food Yellow 3 (II b) and C. I. Acid Red 88 (II c). As the quantity of I added to the aqueous solution of II in a given concentration increased, the molar extinction coefficient of II decreased, reached the minimum at a certain quantity of I, and then began to increase. The lower acidity of the aqueous solution of II, the more quantity of I was required to reach the minimum of molar extinction coefficient. No change of the spectrum was observed even by the addition of poly-l-vinyl-2-pyrrolidone. The saturated binding quantities of acid dyes to copolymers were obtained by dialysis equilibrium. Their caluculated values were higher than those determined from the degree of dissociation by potentiometric titration, and hence the significant amount of dyes were absorbed to copolymerwith mechanism other than ionic bonding.These observations indicate that the bonding between I and II is principally ionic in character, although to some extent II is aggregated around I by absorption.

各種のアゾ染料を塩化第一スズ, 亜硫酸ナトリウムで還元し, その反応溶液の可視スペクトルを測定した。その結果, アゾ染料の還元性についてつぎの知見を得た。モノオキシアゾ染料, o,o'-ジオキシアゾ染料, およびそのコバルト錯塩染料を塩化第一スズで還元すると, i)その反応はアミン類生成にまで進み, ヒドラゾ化合物の生成が律速段階になる, ii)一連の供試アゾ型分散染料における還元速度と置換基との関係は, ハメット則に適合しρは正となる, iii)o,o'-ジオキシアゾ染料に比してそのコパルト錯塩染料は還元の活性化エネルギーが大である。また供試酸性アゾ染料を亜硫酸ナトリウムで還元すると, i)比較的低温度では反応の第一段階でヒドラゾ化合物を生成し, その後徐々にアミン類を生成する, ii)アミン類生成の活性化エネルギーはヒドラゾ化合物生成の活性化エネルギーに比して高い。

The behavior of aromatic sulfonic acids in the aqueous solution was studied in relation to the molecular structure.The mobilities of the aromatic sulfonate ions were measured by the Tiselius electrophoretic apparatus.The mobilities of the disulfonate ions were found to be much larger than that of the monosulfonate ions. This may be due to the larger charge quantity as well as the larger disturbance of arrangement of surrounding water of aromatic rings of disulonic acid than those in the monosulfonate. But the rate of increment of mobilities with the increase of concentration of disulfonate ions were equal or less than that of monosulfonate ions in spite of the larger reduction of ionic atmosphere. This difference may be ascribed to the repulsion of sulfonate ions themselves. The larger the concentration of the sulfonate ion in the aqueous solution of sodium chloride of definite amount, the larger the mobility of the respective ion. A factor explaining this phenomenon may be the increase in effective charge induced by the decrease of ratios of sulfonate and sodium chloride. When the groups such as NH2 or OH are introduced into aromatic ring, the ratio of increment of the mobility increased. For this observation a rationale is advanced in which the disturbance of arrangement of surrounding water of aromatic ring by these groups causes the increase of mobility. The mobility of benzidine systems as well as aniline systems coupled with the same aromatic sulfonic acid in addition to the aromatic sulfonic acid itself were compared and the results are obtained in which the ratio of increment of mobilities increase in the order of; aromatic sulfonic acid, aniline systems, benzidine systems.

The interaction between water-soluble proteins and acid dyes was investigated spectrophotometrically, where the crystalline bovine serum albumin (Ia) and egg albumin (Ib) were used. The acid dyes used were C. I. Acid Orange 7 (IIa), C. I. Mordant Violet 5 (IIb), C. I. Acid Red 178 (IIc), Acid Complex Violet 4R (IId) and C. I. Acid Blue 158 (IIe). The absorption spectra were measured with aqueous solutions of different concentrations of Ia and Ib. The absorption intensities of IIaand IIb at λmax, respectively, decreased in low concentration of albumin, reached the minimumat certain amount of I, and they began to increase with increase in I. In the case of IIc, however, the absorption intensity at the concentration of 4.3×10-5mol/l did not decrease until the added Ia reached 2.0×10-3g/l, and increased markedly from this point. The higher pH, the more quantity of I was required to reach the minimum absorption intensity of II. More quantity of Ib was required than Ia, since the charge Ib is lower than that of Ia. No significant change was observed in the spectrum of the aqueous solutions of IId and IIe upon addition of various amounts of I. The association equilibrium exists between monomer and dimer in the aqueous solutions of IIa, IIb and IIc. But IId and IIe could not be measured owing to little change.In view of the observations on basic vinyl copolymer, it may be concluded that the bonding between I and II is ionic in character and changes in absorption intensity are attributable to the changes in aggregation of II on I.

The reactions of 2-thiouracils and azauracils with ozone have been examined. 2-Thiouracils were ozonized to give the corresponding 4(3H)-pyrimidinones and uracils. Ozone attacks the thiocarbonyl moiety and the desulfurization process to give 4(3H)-pyrimidinones competes with the oxidation process to give uracils. 5-Azauracil was stable for ozone, while 6-azauracil readily reacted with ozone to give parabanic acid.

The reactions of Schiff bases such as N-benzylideneanilines with superoxide ion in acetonitrile under mild conditions gave the cyanomethyl adducts, 3-arylamino-3-arylpropionitriles, as the main products in relatively good yields. In the case of N-(4-nitrobenzylidene)aniline, the adduct was further oxidized to β-anilino-4-nitrocinnamonitrile. No oxidative products such as amides were obtained except in the reactions of N-(4-chloro- and 4-nitrobenzylidene)aniline.

With p-aminoazobenzene as a model compound of basic azo dyes, the ozonation reaction in water at room temperature was examined in the presence of hydrochloric acid. The ozonation gave phenol, p-chloroaniline and p-nitroazobenzene. Ozone would attack azo and hydrazo type of p-aminoazobenzene

In chlorinated solvents, 3-methyl-1-phenyl-4-phenylazo-5-pyrazolone (1) easily reacts with ozone to give benzene (2), phenol (3), chlorobenzene (4), o-chlorophenol (5), biphenyl (6), and 3-methyl-1...

Irradiation of a TiO2 powder suspension in a methanolic solution of an azobenzene results in the formation of 1,2,4-triphenyl-1,2,4-triazolidines and a 2-phenylindazole in moderate yields.

When chalcones were treated with potassium superoxide (KO2) in acetonitrile under ultrasound irradiation, chalcone-acetonitrile adducts were obtained in moderate yields.

Ultrasonic irradiation of α,β-unsaturated carbonyl compounds 1a–i with acetonitrile in the presence of potassium t-butoxide gave 3-cyano-2-methylpyridines 2a–i in moderate to good yields. The pyridines are produced by a Michael reaction of 3-iminobutanonitrile, an acetonitrile dimer, to the substrates 1a–i.

The reactions of 2-thiouracils and azauracils with ozone have been examined. 2-Thiouracils were ozonized to give the corresponding 4(3H)-pyrimidinones and uracils. Ozone attacks the thiocarbonyl moiety and the desulfurization process to give 4(3H)-pyrimidinones competes with the oxidation process to give uracils. 5-Azauracil was stable for ozone, while 6-azauracil readily reacted with ozone to give parabanic acid.

Ozonization of azobenzenes in chlorinated solvents gave 2-chloroazobenzene, 4-chloroazobenzene, azoxybenzene, glyoxal and hygroscopic compounds, whilst similar reaction of phenylazonaphthalenes and azonaphthalenes gave only limited formation of azoxy derivatives. The reaction of a series of azobenzenes with ozone to give azoxybenzenes was investigated with particular respect to substituent and solvent effects.

Bathochromic thiazolylazo second-order nonlinear optical chromophores (NLOphores) having 2-hydroxyethyl group(s) in a molecule have been prepared. The tris(2-hydroxyethyl) derivatives showed the best relaxation behaviour among the non-, mono-, bis- and tris(2-hydroxyethyl) ones doped in poly(methyl methacrylate-co-methacrylic acid).

4-Perfluoroalkylsulfonyl (RfSO2)-substituted azo nonlinear optical chromophores (NLOphores) showed enhanced second-order nonlinear coefficients (d33) and improved relaxation behavior compared with the corresponding nitro compound (Disperse Red 1 (DR 1)) in both doped poly(methylmethacrylate) (PMMA) and pendanted methylmethacrylate (MMA) copolymer.

Perfluoroalkyl-substituted benzothiazolyl bisazo dyes showed higher solubility and greater bathochromicity than the corresponding alkyl derivatives. These dyes showed good dichroism (order parameter S>0.75).

The perfluorobutyl derivative showed a large second-order nonlinear optical coefficient ( d 33 ) and improved relaxation behavior in a series of 6-substituted benzothiazolylazo nonlinear optical chromophores (NLOphores).

Novel disazo dyes containing tetrafluoro-p-phenylene moiety(ies) have been synthesized. The absorption bands of these compounds were observed in the range of 432−555 nm in ZLI-4792. The introduction of tetrafluoro-p-phenylene moieties in both the terminal ends was very effective in increasing the solubility. The 4-butylthio derivative was most soluble among the 4-(butylthio)-, 4-(alkoxy)-, and 4-(butylamino)tetrafluoro-p-phenylene derivatives. The dichroisms of all the tetrafluoro-p-phenylene derivatives were similar (S = 0.69−0.77) to those of the p-phenylene derivatives (0.68−0.76). These results indicate that the novel fluorine-containing disazo dyes can be practically used as dichroic dyes in guest−host liquid crystal displays.