Kakuhiro Kawaguchi

A Solid-State Fluorescent Host System with a 21-Helical Column Consisting of Chiral (1R,2S)-2-Amino-1,2-diphenylethanol and Fluorescent 1-Pyrenecarboxylic Acid

A solid-state fluorescent host system was created by self-assembly of a 2(1)-helical columnar organic fluorophore composed of (1R,2S)-2-amino-1,2-diphenylethanol and fluorescent 1-pyrenecarboxylic acid. This host system has a characteristic 2(1)-helical columnar hydrogen- and ionic-bonded network. Channel-like cavities are formed by self-assembly of this column, and various guest molecules can be included by tuning the packing of this column. Moreover, the solid-state fluorescence of this host system can change according to the included guest molecules. This occurs because of the change in the relative arrangement of the pyrene rings as they adjust to the tuning of the packing of the shared 2(1)-helical column, according to the size of the included guest molecules. Therefore, this host system can recognize slight differences in molecular size and shape.

Control of circularly polarized luminescence (CPL) properties by supramolecular complexation

The sign of circularly polarized luminescence (CPL) of a chiral 21-helical columnar organic fluorophore was successfully controlled in the solid-state by changing an achiral fluorescence component molecule, and not by using a chiral component molecule with opposite chirality.

Multiple molecular response columnar host system composed of rac-2-amino-1,2-diphenylethanol and 1-fluorenecarboxylic acid

By using racemic (rac)-2-amino-1,2-diphenylethanol and achiral fluorescent 1-fluorenecarboxylic acid, a two-component columnar host system with multiple molecular response (guest-dependent spontaneous resolution and fluorescence) properties in the solid state was created.

Chiral channel-like cavity which is tunable via changes in 21-column packing structure

A complex with a chiral channel-like cavity which can incorporate various n-alkyl alcohols and reversibly discharge and adsorb them, was successfully formed by combining chiral 1,2-diphenylethylenediamine ((1S,2S)-1) and biphenylacetic acid (2).

Guest Inclusion Style of 9,10-Diphenylanthracene

9,10-Diphenylanthracene (DPA) permits the inclusion of guest molecules (hexafluorobenzene and 1,4-dioxane) by changing the arrangement of its two-dimensional layers and the size of the cavities formed by these layers in a solid state. In particular, the 1,4-dioxane guest molecules are trapped along the cavities by CH-π interactions with DPA. Crystal data for hexafluorobenzene inclusion complex in DPA, triclinic, space group , a = 6.118(2), b = 7.571(2), c = 12.982(4) Å, α = 78.366(4)°, β = 85.001(5)°, γ = 81.687(5)°, U = 581.7(3) Å3, Z = 2. Crystal data for 1,4-dioxane inclusion complex in DPA, triclinic, space group , a = 5.931(1), b = 7.625(1), c = 12.103(1) Å, α = 85.404(2)°, β = 76.300(2)°, γ = 82.909(2)°, U = 526.96(9) Å3, Z = 2.