東京工業大学 · Materials Science
후쿠하라 가쿠 교수의 연구실은 주로 초분자화학과 광화학을 기반으로 한 다이내믹한 분자 시스템의 설계 및 기능 제어를 연구합니다. 특히, 압력이나 온도와 같은 외부 자극에 의해 변화하는 입체화학적 성질과 광학적 특성(예: 기함성, CD 신호, 플루오레스센스)을 제어하는 초분자 복합체 개발에 초점을 맞추고 있으며, 이는 센서, 이미징 재료 및 스마트 재료 응용에 기여합니다. 연구는 주로 사이클로덱스트린 衍생체, 사이클로파노필라르렌 유도체, 그리고 고분자 기반 초분자 복합체를 대상으로 하여, 분자 내 상호작용과 구조-기능 관계를 깊이 있게 규명합니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
Planar chiral cyclophanopillar[5]arenes with a fused oligo(oxyethylene) or polymethylene subring (<b>MUJ</b>s), existing as an equilibrium mixture of subring-included (in) and -excluded (out) conformers, respond to hydrostatic pressure to exhibit dynamic chiroptical property changes, leading to an unprecedented pressure-driven chirality inversion and the largest ever-reported leap of anisotropy (<i>g</i>) factor for the <b>MUJ</b> with a dodecamethylene subring. The pressure susceptivity of <b>M
An in situ hybrid complex of Curdlan with water-soluble polythiophene functioned as a highly sensitive and selective saccharide chemosensor in aqueous media, enabling us to discriminate tetrasaccharide acarbose at 1 μM from 24 mono-, di-, tri-, tetra-, and pentasaccharides.
Permethylated 6-O-modified beta-cyclodextrins 2a-2d were synthesized as novel photosensitizing hosts with a flexible skeleton. Circular dichroism (CD) and 2D NMR spectral examinations of benzoate 2a revealed that the benzoate moiety is deeply included into its own cavity in aqueous solution. Upon addition of (Z)-cyclooctene (1Z) to a 50% aqueous methanol solution of 2a at 25 degrees C, the benzoate moiety of 2a was gradually excluded from the cavity as indicated by the CD spectral changes; the J
In contrast to the photosensitization with a non-methylated analogue, supramolecular photochirogenesis with a novel permethylated mono(6-O-benzoyl)-beta-cyclodextrin exhibited a critical dependence of the product's enantiomeric excess upon temperature, and possessed a large differential entropy of activation (-11 J K(-1) mol(-1)) for which the flexible host skeleton is likely to be responsible.
Abstract Understanding changes in excited state properties under the influence of an external stimulus, such as pressure or temperature, is important in the context of optimizing molecular components for a number of applications including sensors and imaging reagents. Herein, we use UV/Vis absorption, fluorescence and excitation spectroscopies and fluorescence lifetime measurements supported by calculations to probe the effect of hydrostatic pressure on the excited state characteristics of a con
UV-vis, circular dichroism (CD), fluorescence, and NMR spectral studies on the self-inclusion behavior of a newly synthesized sensitizing host, 6-(5-cyanonaphthyl-1-carboamido)-6-deoxy-beta-cyclodextrin (1), showed that the appended naphthalene moiety of 1 perches laterally on the cyclodextrin rim in aqueous methanol but is shallowly included and somewhat tilted in its own cavity in water. UV-vis and CD spectral examinations of the complexation of guest substrate 1,1-diphenylpropene (DPP) with h
An enantiomeric binaphthyl unit was tethered to adjacent thiophenes with oxyethylene linkers to give a chiral polythiophene with binaphthocrown ether cavities. Upon inclusion of a chiral cationic guest in the cavity of the chiral crown ether-polythiophene conjugate, the bithiophene unit was twisted to shorten the effective conjugation length of polythiophene backbone, enabling us to sense the guest binding by reading out the amplified optical signal gains arising from the backbone structure chan
Near-perfect stereoselectivity was attained in the diastereodifferentiating [4 + 4] photocyclodimerization of 2-anthracenecarboxylates tethered to a glucose scaffold not by thermodynamically tuning the conformer equilibrium in the ground state but by kinetically controlling the conformer dynamics and reactivity in the excited state, which enabled us, after removal of the scaffold, to obtain a single enantiomer of chiral anti-head-to-head-cyclodimer in >99% optical and 96% chemical yield from an
A new cyclodextrin-polythiophene conjugate (CDPT) has been prepared by attaching permethyl-α-cyclodextrins to polythiophene (PT) through a hexamethylene tether. Circular dichroism spectral examination of CDPT revealed that only a weak positive Cotton effect (Δε=0.1 M(-1) cm(-1)) was induced at the main band of the PT in dimethyl sulfoxide and similarly weak bisignate signals in pure and aqueous methanol solutions, which indicates that the α-cyclodextrins appended to PT with a long tether are ine
A newly synthesized chromophore-modified curdlan functions as a saccharide chemosensor in aqueous solution, enabling us to discriminate tetrasaccharide acarbose from 24 mono-, di-, tri-, and tetrasaccharides.
Abstract In contrast to a standard steady fluorescence intensity increase of a chloroform solution of a linear chromophore unit under high pressure, a fluorescent cyclophane solution shows significant fluorescence quenching under elevated pressure. A pressure‐induced enhancement of the formation of an intramolecular π‐stacked conformation is proposed to be responsible.
Pressure (<i>P</i>), as one of the most inherent state quantities, has become an academic subject of study and has attracted attention for a long time for the minute control of reaction equilibria and rates, not only in the gas phase, based on the gas state equation, but also in the solution state. In the latter case, the pressure applied to the solutions is classified as hydrostatic pressure, which is a type of isotropic mechanical force. For instance, deep-sea organisms are exposed to hydrosta
