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The Lewis base-promoted alkynylation of fluorobenzenes using trimethylsilylacetylenes studying the reactivity as a function of the number of fluoride groups is described. The reaction of 1-(pentafluorophenyl)- and 1-(3,4,5-trifluorophenyl)-2-phenylacetylenes and 1-(4-methoxyphenyl)-2-trimethylsilylacetylene with CsF/18-crown-6 in DMSO gave the alkynylated products in moderate to good yields with high regioselectivity under mild conditions. However, the 3,4-difluorophenyl derivative showed low reactivity.

Novel 2-cyanoviologen derivatives having highly anodically shifted reduction potentials were synthesized. The colors of their cation radicals showed a variety of colors as same as those of corresponding viologen derivatives.

Several molecules having multiple regions independently responsive to stimulations have been investigated. A 2-(4-methoxyphenylazo)anthraquinone (1) having both an electrochromic quinone group and a photochromic azo group has been synthesized and its electrochromic and photochromic properties investigated. It shows interconversion of four distinct states caused by multiplication of two electrochromic redox states, quinone and hydroquinone, and two photochromic geometrical isomers, anti and syn forms. Moreover the syn-anti thermal isomerization rate of the azo region of the molecule is dependent on the state of the electrochromic quinone region. The rate for the quinone form is more than 30 times faster than that of the hydroquinone form. Additionally three other azoquinone compounds have been synthesized and investigated in the same way. The results show that these molecules have functions of multiple responsibilities for distinguishable stimulations as multi-mode chemical signal transducers.

A simple and general synthetic strategy potentially applicable for the preparation of a wide variety of unsymmetrically N,N'-bis(substituted)-4, 13-diaza-18-crown-6-ether derivatives was reported.

Novel synthesis of π-conjugated molecules by cross-metathesis reaction of vinylferrocene with a series of vinylarenes was investigated with a molybdenum-based Schrock catalyst (CHCMe2Ph)Mo(N-2,6-i-Pr2C6H3)[OCMe(CF3)2]2. The cross-metathesis reactions occurred successfully and the cross-metathesis product, i.e., heterodimers, were readily obtained selectively, together with only small amounts of the corresponding self-dimers.

A novel photochromic hexaarylbiimidazole with a bithienyl group as an extended π-conjugation unit was synthesized and the light-induced lophyl radical was found to be stabilized due to the delocalization of an unpaired electron, and to strongly absorb near-infrared light.