1,1'-ビナフチル・ブリッジド・フェノキシル・イミダゾリル・ラジカル・コンプレクスの素早い負の光色化

Tetsuo Yamaguchi¹, Yoichi Kobayashi¹, Jiro Abe¹

¹Department of Chemistry, School of Science and Engineering, Aoyama Gakuin University , 5-10-1 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5258, Japan.

Journal of the American Chemical Society

|December 30, 2015

まとめ

研究者は新しいネガティブな光色化合物BN-PICを開発し,高速な光スイッチングを行いました. この材料は,可視光で急速な色変化と,高度な光反応性アプリケーションに理想的な迅速な熱反応を示します.

科学分野:

材料科学
写真化学
有機化学

背景:

ネガティブ・フォトクロミズムは,可視光による色変化を可能にし,内部材料の適用に有益である.
既存のネガティブ光色化合物は,遅い熱反射時間 (分) を表しています.
先進的な用途のために,迅速に反応するネガティブ光色材料が必要である.

研究の目的:

新種のネガティブ・フォトクロミック・コンパウンドを開発する
新しい化合物の光色特性と熱反射運動を調査する.
光色反応にキラリティの影響を調べるため

主な方法:

1,1'-ビナフチルブリッジのフェノキシル-イミダゾリル基複合体 (BN-PIC) の合成
可視光照射を用いた光色交換実験
室温での熱反射の運動研究
カイロプティック特性測定と溶媒のキラリティ効果分析

主要な成果:

BN-PICは可視光にさらされた瞬間の変色を示しています.
BN- PICの光生成された無色形態は,室温で半減期1. 9秒で有色形態に戻ります.
フォトクロミック反応の間,カイロプティック特性の有意な変化が観察されました.
熱反射の速度は溶媒のキラリティによって影響を受けます.

結論:

迅速に反応する新しいネガティブ光色化合物 (BN-PIC) が開発されました.
BN-PICは,可視光による急速な光スイッチングを可能にし,迅速な熱反射を示します.
カイロプティックな性質と溶媒のキラリティに影響を及ぼす化合物の能力は,キラルの光反応性物質のための新しい道を開きます.

さらに関連する動画

09:12

[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst

Published on: May 21, 2019

10.0K

10:21

Developing Photosensitizer-Cobaloxime Hybrids for Solar-Driven H2 Production in Aqueous Aerobic Conditions

Published on: October 5, 2019

9.1K

関連する概念動画

01:26

Photochemical Electrocyclic Reactions: Stereochemistry

2.4K

The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation

2.4K

01:17

Oxidation of Phenols to Quinones

5.2K

In the presence of oxidizing agents, phenols are oxidized to quinones. Quinones can be easily reduced back to phenols using mild reducing agents. The electron-donating hydroxyl group enhances the reactivity of the aromatic ring, enabling oxidation of the ring even in the absence of an α hydrogen.
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...

5.2K

01:26

Thermal and Photochemical Electrocyclic Reactions: Overview

3.2K

Electrocyclic reactions are reversible reactions. They involve an intramolecular cyclization or ring-opening of a conjugated polyene. Shown below are two examples of electrocyclic reactions. In the first reaction, the formation of the cyclic product is favored. In contrast, in the second reaction, ring-opening is favored due to the high ring strain associated with cyclobutene formation.

3.2K

01:29

The Photochemical Reaction Center

5.9K

Reaction centers are pigment-protein complexes that initiate energy conversion from photons to chemical entities. Therefore, photochemical reaction center is a more appropriate term that describes these complexes. The Nobel laureates Robert Emerson and William Arnold provided the first experimental evidence of photochemical reaction centers by demonstrating the participation of nearly 2,500 chlorophyll molecules for the release of just one molecule of oxygen. Despite thousands of photosynthetic...

5.9K

01:17

Electron Paramagnetic Resonance (EPR) Spectroscopy: Organic Radicals

3.7K

Ideally, an unpaired electron shows a single peak in the EPR spectrum due to the transition between the two spin energy states. However, coupling interactions can occur between the spins of the unpaired electron and any neighboring spin-active nuclei. This hyperfine coupling results in hyperfine splitting, where the EPR signal is split into multiplets. The signals split into 2nI + 1 peaks, where n is the number of equivalent nuclei and I is the nuclear spin. These splitting patterns provide...

3.7K

01:22

Photoreceptors and Visual Pathways

11.0K

At the molecular level, visual signals trigger transformations in photopigment molecules, resulting in changes in the photoreceptor cell's membrane potential. The photon's energy level is denoted by its wavelength, with each specific wavelength of visible light associated with a distinct color. The spectral range of visible light, classified as electromagnetic radiation, spans from 380 to 720 nm. Electromagnetic radiation wavelengths exceeding 720 nm fall under the infrared category,...