ポルフィリンが4つのアントラセネスと融合した
Nicola K S Davis1, Amber L Thompson, Harry L Anderson
1Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, UK.
Journal of the American Chemical Society
|December 15, 2010
まとめ
研究者らは,新しい溶融テトラアントラセニルポルフィリンを合成した. この新しいポルフィリン誘導体は,強烈な近赤外線吸収と小さなエネルギーギャップを含むユニークな光学および電子特性を示しており,先進的な材料のアプリケーションに有望です.
科学分野:
- マテリアルサイエンス 材料科学
- 有機化学 オーガニック・ケミストリー
- フォトケミストリー フォトケミストリー
背景:
- ポルフィリンは,多様な用途を持つ多用途のマクロサイクル化合物です.
- アントラセンと融合したポルフィリンは,ユニークな光物理的特性を有しています.
- ポルフィリン内の電子構造を調節することは,高度な材料の鍵です.
研究 の 目的:
- 新しく融合したテトラアントラセニルポルフィリンを合成するために.
- その光学および電気化学的性質を特徴付けるために.
- 固体構造と分子間相互作用を調査する.
主な方法:
- メソアンスラセニルニッケル (メソアンスラセニルニッケル) の酸化による化学合成 (II) ポルフィリン.
- スペクトル分析 (UV-Vis吸収).
- HOMO-LUMOギャップを測定するために,電気化学測定 (サイクル電圧測定) を行う.
- 結晶構造を決定するX線結晶学.
主要な成果:
- 溶融したテトラアントラセニルポルフィーリンの合成が成功しました.
- 濃度の近赤外線吸収スペクトルで,λ (max) = 1417 nmと高モラ吸収率 (ε = 1.2 × 10 ((5) M ((-1) cm ((-1)) を有する.
- 0.61 eVの小さな電気化学のHOMO-LUMOギャップです.
- 結晶構造は,3.32 Å の短い Ni··Ni 距離を持つ π 積み重ねのダイマーを明らかにしました.
結論:
- 合成された溶融テトラアントラセニルポルフィリンは,ユニークな光電子特性を持っています.
- 観測された π スタッキングと短い Ni-Ni 距離は,その電子行動に影響します.
- この化合物は,有機電子と光学における応用の可能性を秘めています.
関連する概念動画
Five-Membered Heterocyclic Aromatic Compounds: Overview
Heterocyclic aromatic compounds are cyclic compounds that are aromatic and have one or more heteroatoms—atoms other than carbon, in the ring. Depending upon the number of atoms present in the ring, they can be either five or six-membered. Examples of five-membered heterocyclic aromatic compounds include pyrrole, furan, thiophene, and imidazole. Pyrrole consists of one nitrogen atom having one lone pair of electrons. Furan and thiophene have one oxygen and one sulfur heteroatom, respectively.
Aromatic Hydrocarbon Cations: Structural Overview
Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group with both...
Removing one hydrogen from the intervening CH2 group with both...
The Antenna Complex
Plants and other photosynthetic organisms comprise pigments capable of absorption of direct sunlight. These pigments are present in the reaction center - the main site of photochemical reactions as well as in the antenna complex. Under average light conditions, the rate at which reaction center pigments absorb light is far below the electron transport chain's capacity. As a result, the reaction center alone cannot provide enough energy to drive photosynthesis. The photosynthetic efficiency can...
Aromatic Hydrocarbon Anions: Structural Overview
Neutral hydrocarbons like cyclopentadiene with an odd number of carbon atoms and one intervening CH2 group in the ring are not aromatic. Cyclopentadiene with 4 π electrons does not satisfy the 4n + 2 π electron rule. Additionally, the intervening CH2 group is sp3 hybridized and lacks a vacant p orbital, thereby interrupting the overlap of p orbitals in a continuous manner and preventing the delocalization of π electrons throughout the ring.
Due to the absence of continuous overlap of p...
Due to the absence of continuous overlap of p...
Criteria for Aromaticity and the Hückel 4n + 2 Rule
Like benzene, cyclobutadiene and cyclooctatetraene are cyclic compounds with alternate single and double bonds. However, their chemical behavior differs from benzene, as they are unstable and not aromatic. So, what are the structural characteristics of unsaturated compounds categorized as aromatic?
For the first time, Eric Hückel, a German chemical physicist, derived a set of structural features for a compound to be classified as aromatic. This is now known as Hückel’s rule or the 4n + 2 rule.
For the first time, Eric Hückel, a German chemical physicist, derived a set of structural features for a compound to be classified as aromatic. This is now known as Hückel’s rule or the 4n + 2 rule.
Photosystem I
Although structurally similar to photosystem II (PSII), photosystem I (PSI) is has a different electron supplier and electron acceptor.
Both these photosystems work in concert. An excited electron from PSII is relayed to PSI via an electron transport chain in the thylakoid membrane of the chloroplast, which is comprised of the carrier molecule plastoquinone, the dual-protein cytochrome complex, and plastocyanin. As electrons move between PSII and PSI, they lose energy and must be re-energized...
Both these photosystems work in concert. An excited electron from PSII is relayed to PSI via an electron transport chain in the thylakoid membrane of the chloroplast, which is comprised of the carrier molecule plastoquinone, the dual-protein cytochrome complex, and plastocyanin. As electrons move between PSII and PSI, they lose energy and must be re-energized...
![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)

![[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)