Satoru Mori

Efficient synthesis of unsymmetrical S-(bromodifluoromethyl)diarylsulfonium salts for electrophilic bromodifluoromethylating reagents

A series of unsymmetrical S-(bromodifluoromethyl)diarylsulfonium salts 1 were readily synthesized by treatment of corresponding (bromodifluoromethyl)arylsulfoxides 2 and substituted benzenes 3 with triflic anhydride in moderate to good yields. The unsymmetrical sulfonium salts 1 with different aryl groups having electron-donating or electron-withdrawing substituents can be nicely constructed depending on the choice of 2 and 3. Bromodifluoromethylation of alkynes was evaluated by using the selected diarylsulfonium salts 1 to provide the desired bromodifluoromethylated alkynes in moderate to good yields.

Synthesis of Phthalocyanines with a Pentafluorosulfanyl Substituent at Peripheral Positions.

Abstract The pentafluorosulfanyl (SF5) group is more electronegative, lipophilic and sterically bulky relative to the well‐explored trifluoromethyl (CF3) group. As such, the SF5 group could offer access to pharmaceuticals, agrochemicals and optoelectronic materials with novel properties. Here, the first synthesis of phthalocyanines (Pcs), a class of compounds used as dyes and with potential as photodynamic therapeutics, with a SF5 group directly attached on their peripheral positions is disclosed. The key for this work is the preparation of a series of SF5‐containing phthalonitriles, which was beautifully regio‐controlled by a stepwise cyanation via ortho‐lithiation/iodination from commercially available pentafluorosulfanyl arenes. The macrocyclization of the SF5‐containing phthalonitriles to SF5‐substituted Pcs required harsh conditions with the exception of the synthesis of β‐SF5‐substituted Pc. The regiospecificity of the newly developed SF5‐substituted Pcs observed by UV/Vis spectra and fluorescence quantum yields depend on the peripheral positon of the SF5 group.

Acceleration by MS-818 of early muscle regeneration and enhanced muscle recovery after surgical transection.

The synthesized pyrimidine compound MS‐818 has neurotrophic effects in several kinds of neuronal cells, but its effect with respect to muscle cells remains unknown. We therefore examined the effects of MS‐818 on regeneration for 12 weeks in a wounded area (damaged and gap areas) of cut muscle in adult rats. The right semitendinosus muscles of reated and control groups were severed and sutured at the belly and the left semitendinosus muscles were left intact. MS‐818 was administered intraperitoneally to the treated group at a dose of 5 mg/kg once daily. Control rats received an equal volume of physiological saline. A reference group underwent no surgical procedure. MS‐818 significantly increased the maximal isometric twitch tension (Tmax) compared to control and reference rats after week 4 (approximately 1.4‐fold control value; 0.6‐fold reference value). Northern blotting showed that MS‐818 enhanced myogenin mRNA expression to about 1.5‐fold above the control level at 2, 4, and 7 days after surgery. Immunohistochemical and histochemical studies showed significant enhancement in the treated group since myogenic cells expressed desmin and were positive for neonatal myosin, and the fiber diameters and numbers of premature myofibers and end plates were increased when compared with those in the control group. These results show that MS‐818 accelerated the proliferation and differentiation of activated satellite cells and the fusion of myotubes to form immature myofibers. At week 12, Tmax, fiber diameter, and number of end plates in the treatment group recovered 60, 85, and more than 100%, respectively, compared to the reference group. The mechanism of MS‐818 effects on the accelerated regeneration of cut muscle is discussed.

Synthesis and optical properties of trifluoroethoxy-substituted double-decker phthalocyanines

The synthesis of trifluoroethoxy-substituted double-decker phthalocyanines was investigated for the first time. Trifluoroethoxy-substituted phthalonitriles reacted with lanthanide acetylacetonate hydrate in n-octanol in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene when refluxed. La and Eu were chosen as central metals. Phthalonitriles, including one trifluoroethoxy substituent at the α- or β-position, were nicely induced to double-decker phthalocyanines. Phthalonitrile having two trifluoroethoxy substituents at α-positions did not react, although we succeeded in leading β-di-substituted phthalonitrile to double-decker phthalocyanines. Fully trifluoroethoxy-coated phthalonitrile did not react at all. Fluorophobic repulsion and steric hindrance caused by outlying trifluoroethoxy groups could be responsible for the difficulty in the formation of a double-decker structure. Absorption and fluorescence spectra of trifluoroethoxy-substituted double-decker phthalocyanines obtained were also investigated.

Synthesis and application of trifluoroethoxy-substituted phthalocyanines and subphthalocyanines

Phthalocyanines and subphthalocyanines are attracting attention as functional dyes that are applicable to organic solar cells, photodynamic therapy, organic electronic devices, and other applications. However, phthalocyanines are generally difficult to handle due to their strong ability to aggregate, so this property must be controlled for further applications of phthalocyanines. On the other hand, trifluoroethoxy-substituted phthalocyanines are known to suppress aggregation due to repulsion of the trifluoroethoxy group. Furthermore, the electronic characteristics of phthalocyanines are significantly changed by the strong electronegativity of fluorine. Therefore, it is expected that trifluoroethoxy-substituted phthalocyanines can be applied to new industrial fields. This review summarizes the synthesis and application of trifluoroethoxy-substituted phthalocyanine and subphthalocyanine derivatives.

Super-Sensitive Protonation Behavior of Trifluoroethoxy-Substituted Phthalocyanines and Their Application to Solvent Discrimination

The super-sensitive protonation behavior of trifluoroethoxy-substituted phthalocyanines (TFEO-Pcs) was carefully studied using UV–vis and fluorescence spectroscopy, as well as computational calculations. The practical utility of TFEO-Pcs in sensor technology was demonstrated by identifying chloroform samples from different commercial sources.