Search

Reactions of phenyldiazomethane with chloranil and of 1-phenyldiazoethane and 9-diazofluorene with 2,3-dichloro-5,6-dicyano-p-benzoquinone in the presence of oligoethylene glycols and its monomethyl ethers gave the corresponding substituted crown ether acetals and open-chain analogues.

The reactions of several aryldiazomethanes (1a: p-tolyl; 1b: phenyl; 1c: p-chlorophenyl) with chloranil gave stilbenes (3) and spiro-oxetanes (4) at 20 °C in tetrahydrofuran or 1,2-dichloroethane. The isomer ratios of 3 were ca. 2 to 3:1 in favor of cis, depending on the solvents and on the substituents of 1. In the case of 4, however, stable trans-isomers were selectively formed. On the other hand, the presence of added CH3OH suppressed the formations of 3 and 4 and, instead, induced redox reactions giving α,α-dimethoxyarylmethanes and tetrachlorohydroquinone (6). In these redox reactions, the acid decompositions of 1 with 6 were also found. However, the presence of CF3CH2OH allowed the formation of considerable amount of 3 and 4, along with the redox products. The mechanism of these reactions will be discussed.

It was found that a number of diazoalkanes (I) bearing a relatively small substituent reacted with o-sulfobenzoic anhydride (II) in acetonitrile at an ordinary temperature to give the o-(substituted glycoloyl)benzenesulfonic acid sultones (IV), which correspond formally to the products from the insertion into the C–O bond of II by the carbenes, while diaryldiazomethanes underwent decomposition under the same conditions to produce the corresponding tetraarylethylenes (V) instead of the inserted products (IV). The olefin formation reaction was very fast compared to the sultone formation and was considered to be the result of the acid-catalyzed decomposition caused by the contaminant o-sulfobenzoic acid (III) which was derived from II. The kinetics and the mechanism of these reactions were discussed on the basis of the nature of diazoalkanes.

Unsubstituted 1,4-benzoquinone (1a) reacted at the C=C double bond with 9-diazofluorene (9-DF) to give norcarene dione 2a and 4,7-dihydroxy-3H-indazole 4a. Similarly, the reaction of 2-chloro-1,4-benzoquinone (1b) with 9-DF yielded norcarene dione 2b and 4,7-dihydroxy-3H-indazole 4b, together with tricyclic dione 3b. 2,3-dichloro-1,4-benzoquinone (1c) and 9-DF produced norcarene dione 2c, 4,7-dihydroxy-3H-indazole 4c, and its fluorenyl ether 5c. Reactions of 2,5- and 2,6-dichloro- and trichloro-1,4-benzoquinones (1d, 1e, and 1f) with 9-DF provided norcarene diones 2d, 2e, and 2f and tricyclic diones 3d and 3e, respectively. On the other hand, tetrachloro-1,4-benzoquinone (1g) converted 9-DF into 9,9′-bifluorenylidene possibly via a 1:1 betaine intermediate arising from the C=O double bond addition. These results were markedly different from those of the previous diphenyldiazomethane reactions and are discussed in terms of structural changes of these diazoalkanes.

The therapeutic effects of fullerene derivatives on many models of inflammatory disease have been demonstrated. The anti-inflammatory mechanisms of these nanoparticles remain to be elucidated, though their beneficial roles in allergy and autoimmune diseases suggest their suppressive potential in acquired immunity. Here, we evaluated the effects of C60 pyrrolidine tris-acid (C60-P) and polyhydroxylated fullerene (C60(OH)36) on the acquired immune response in vitro and in vivo. In vitro, both C60 derivatives had dose-dependent suppressive effects on T cell receptor-mediated activation of T cells and antibody production by B cells under anti-CD40/IL-4 stimulation, similar to the actions of the antioxidant N-acetylcysteine. In addition, C60-P suppressed ovalbumin-specific antibody production and ovalbumin-specific T cell responses in vivo, although T cell-independent antibodies responses were not affected by C60-P. Together, our data suggest that fullerene derivatives can suppress acquired immune responses that require T cells.

Eight 2,2-diaryl-1,3-dioxanes were prepared and the kinetic substituent effects regarding acidcatalyzed hydrolysis were studied in 80% dioxane–water(v/v) at 30 °C. The logk were well correlated with the Yukawa-Tsuno equation; logk⁄k0=−2.92(σ0+0.385Δ\barσR+)(r=0.999).

Thermolysis of cis- and trans-spirooxetanes(1)proceeded with 94–100% retention of stereochemistry to give stilbene(2) and quinones(3). Important role of a concerted pathway was assumed.

Reactions of phenyldiazomethane with chloranil and of 1-phenyldiazoethane and 9-diazofluorene with 2,3-dichloro-5,6-dicyano-p-benzoquinone in the presence of oligoethylene glycols and its monomethyl ethers gave the corresponding substituted crown ether acetals and open-chain analogues.

Reaction of 1-phenyldiazoethane(1) with tetrachloro- p -benzoquinone(2) gave 1-alkoxy-4-ethenyloxy-tetrachlorobenzene(4). With tetrachloro- o -benzoquinone(5), 1 provided 1-alkoxy-2-ethenyloxy-tetrachlorobenzene(7) and tetrachlorobenzo-1,3-dioxolane(8). The mechanism and the effect of added methanol were discussed.

The kinetics of the reactions of meta- and para-substituted diazodiphenylmethanes (DDM) with tetracyanoethylene (TCNE) in benzene are reported. The corresponding 1,1-diaryl-2,2,3,3-tetracyanocyclopropanes were produced almost quantitatively and the second-order rate constants k increased with the electron-donating ability of the substituents; the presence of p-OCH3 and p′-CH3 groups resulted in the reaction being ca. 6.5 × 103 times faster than for the m-Cl substituent. At 30 °C, log k=–2.67 σ+–1.23 (r–0.989). E.s.r. measurements showed the presence of the radical anion of TCNE, though the counter radical cation derived from the diazo-compounds could not be detected. The mechanism of these reactions is discussed on the basis of initial electron transfer from the diazo-compound to TCNE.

When 2-, 3-, or 4-benzoylbenzoic acid, 2-(2,4,6-trimethylbenzoyl)benzoic acid, or 2-acetylbenzoic acid and (–)-(R)-amphetamine, (–)-(R)-N-methylamphetamine, (±)-(R)- or (–)-(S)-α-phenylethylamine, or (±)-(S)-s-butylamine were dissolved together in equimolar proportions in the non-polar solvents benzene or carbon tetrachloride at 25°, induced circular dichroism was observed even at low concentrations. The logarithm of the molecular ellipticity θ, of the mixture of 2-benzoylbenzoic acid and amphetamine inversely correlates with the ET value of the solvent used. A contact ion pair derived from salt formation between the keto-acid and the optically active amine may be responsible for the phenomenon. In polar solvents such as alcohol the induced c.d. effect is reduced as expected from increased dissociation of the ion pair.