Straightforward synthesis of 1,2-dicyanoalkanes from nitroalkenes and silyl cyanide mediated by tetrabutylammonium fluoride.

A straightforward synthesis of 1,2-dicyanoalkanes by reacting nitroalkenes with trimethylsilyl cyanide in the presence of tetrabutylammonium fluoride is described. The reaction proceeds through a tandem double Michael addition under mild conditions. Employing the hypervalent silicate generated from trimethylsilyl cyanide and tetrabutylammonium fluoride is essential for achieving this transformation.

Iodoamidation of olefins with chloramine salts and iodine in aqueous media.

An efficient, unique, and convenient method for the iodoamidation of olefins with chloramine salts and I(2) in aqueous media is described. This method was applicable to a wide range of olefins, including aromatic, aliphatic, and electron-deficient olefins.

CO2-induced amidobromination of olefins with bromamine-T.

The carbon dioxide (CO(2))-induced amidobromination of olefins with bromamine-T is described. The method can be used in reactions with a wide range of olefins, both aromatic and aliphatic, as well as electron-rich and deficient olefins, leading to the regioselective formation of amidobrominated compounds.

Solvent effect on the photochemical properties of symmetrically substituted trans-3,3',5,5'-tetramethoxystilbene.

Photochemical properties of trans-3,3',5,5'-tetramethoxystilbene (TMST) have been studied in various polar solvents. The Stokes shift of trans-TMST was found to be increased with increasing solvent polarity. The fluorescence lifetime of trans-TMST experienced a large solvent effect changing from 2.

Inhibition of the formation and decay of stilbene core radical cations by the dendron during the photoinduced electron transfer.

Formation and decay processes of stilbene core radical cation (ST*+) during the photoinduced electron transfer have been studied for a series of stilbene bearing benzyl ether-type dendrons (D). ST*+ and the radical cation of peripheral dendron (D*+) were generated by intermolecular hole transfer from biphenyl radical cation, which was generated from photoinduced electron transfer from biphenyl to the singlet-excited 9,10-dicyanoanthracene in a mixture of acetonitrile and 1,2-dichloroethane (3:1). An intramolecular dimer radical cation of benzyl groups at the terminal of stilbene dendrimer was indicated as a hole trapping site.

Effects of benzyl ether type dendrons as hole-harvesting antennas, and shielding for the neutralization of stilbene core radical cations with chloride ion during two-photon ionization of stilbene dendrimers having stilbene core and benzyl ether type dendrons.

The two-photon ionization (TPI) process (308 and 266 nm) of stilbene dendrimers having a stilbene core and benzyl ether type dendrons has been investigated in an acetonitrile and 1,2-dichloroethane mixture (3:1) in order to elucidate the dendrimer effects. The quantum yield of the formation of stilbene core radical cation during the 308-nm TPI was independent of the dendron generation of the dendrimers, whereas a generation dependence of the quantum yield of the radical cation was observed during the 266-nm TPI, where both the stilbene core and benzyl ether type dendron were ionized, suggesting that the subsequent hole transfer occurs from the dendron to the stilbene core, and that the dendron acts as a hole-harvesting antenna. The neutralization rate of the stilbene core radical cation with the chloride ion, generated from the dissociative electron capture by 1,2-dichloroethane, decreased with the increase in the dendrimer generation, suggesting that the dendron is an effective shield of the stilbene core radical cation against the chloride ion.

Water-soluble stilbene dendrimers.

The third generation of novel photo-responsive water-soluble stilbene dendrimer (trans- and cis-G3 WSD) undergoes unusual one-way trans-to-cis isomerization to give 100% of cis isomer at the photostationary state on UV irradiation in water.