活性S-S結合による結晶相光応答錯体分子の構築と光機能の解明

• Material Type: 文書・図像類
• Title: 活性S-S結合による結晶相光応答錯体分子の構築と光機能の解明
• Author/Editor: 磯辺, 清; Isobe, Kiyoshi
• Author Heading: 磯辺, 清; Isobe, Kiyoshi
• Publication Date: 2010-06-08
• Publication Date (W3CDTF): 2010-06-08
• Alternative Title: Synthesis and Function of Crystalline-state Photoresponsive Metal Complexes with Active S-S Bond
• Periodical title: 平成19(2007)年度 科学研究費補助金 基盤研究(B) 研究成果報告書概要 = 2007 Fiscal Year Final Research Report Summary
• No. or year of volume/issue: 2004 - 2007
• Volume: 2004 - 2007
• Pages: 6p.-
• Text Language Code: jpn
• Subject Heading: 活性S-S結合; 結晶相反応; 光応答機能; フォトクロミズム; 温度可変固体D NMR; 不斉結晶化; 絶対不斉合成; / 光誘起相転移; Active S-S Bond; Crystalline-state Reaction; Photoresponsive Function; Photochromism; Variable Temperature Solid State ^2H NMR Spectroscopy; Chiral Crystalzation; Absolute Asymmetric Synthesis; 光誘起相転移
• Target Audience: 一般
• Note (General): 金沢大学理工研究域; 分子内に2つのCp^*配位子(η^5-C_5Me_5)と光応答機能の担い手となるジチオナイト配位子(μ-O_2SSO_2)を有するロジウム二核錯体[(Cp^*Rh)_2(μ-C(μ-O_2SSO_2))(1)が、結晶相で光応答を示すことを見出した(μ-O_2SSO_2〓μ-0_2SOSO)。錯体1の結晶中のCp^*配位子の運動を詳しく調べるために、Cp^*配位子の水素原子を全て重水素化したCp^<*d15>配位子(η^5-C_5(CD_3)_5)を有する[(Cp^<*d15>Rh)_2(μ-CH_2)_2(μ-O_2SSO_2)〕(1-d_<30>)を合成した。錯体1-d_30の温度可変固体^2H NMR測定とスペクトルの波形解析によって、反応空間を形成する配位子の運動に関する詳細な検討を行った。その結果、(1)Cp^*配位子の運動モードは、「配位子のC_5軸に沿った回転運動」であること、(2)結晶中で非等価な環境にある1分子中の2つのCp^*配位子の回転運動の活性化エネルギーは、33±3と7.8±1kJ/molであることが分かった。さらにCp^*環の化学修飾に成功し、新規ジチオナイト錯体の単結晶フォトクロミズムについて系統的に検討した。温度可変固体^2H-NMRの測定によって、結晶中での光応答空間の動的挙動を詳細に明らかにすることができた。興味あることに、n-プロピル置換基を導入した錯体を用いると、不斉結晶化を利用した絶対不斉光異性化反応が進行することを見出した。また光照射初期の段階で,光相転移がおこることを見いだした。これまでに得られた成果は、国際会議8件、国内の学会25件で発表した。7報の学術論文発表と2件の特許出願を行った。; In the crystalline state, the rhodium dinuclear complex[(RhCp^*)_2(μ-CH_2)_2(μ-O_2SSO_2)] (1) with a photoresponsive dithionite group (μ-O_2SSO_2) and two pentamethylcyclopentadienyl ligands (Cp^*=η^5-C_5Me_5) undergoes a 100% reversible unimolecular type T inverse photochromism upon interconversion to [(RhCp^*)_2(μ-CH_2)_2(μ-O_2SOSO)] (2). The photochromism can be followed directly by using stepwise crystal structure analysis.In this study, we found that the photoreaction of 1 was triggered by absorption of the 510 nm light (charge transfer band from σ(S-S)to σ^*(S-S)and σ^*(Rh-Rh)orbitals assigned by DFT calculation) and included two important processes:kinetically controlled oxygen-atom transfer to produce four stereoisomers of 2 and thermodynamically controlled isomerization between the four stereoisomers of 2 to afford the most stable isomer. Although the formation rate of the four stereoisomer products was kinetically controlled and the population of the four stereoisomers produced in the system was thermodynamically controlled, both processes were regulated by the steric hindrance between the μ-O_2SSO_2 or μ-O_2SOSO ligand and the reaction cavity formed by the Cp^* ligands. The cooperation of both processes achieved an intriguing stereospecific oxygen-atom rearrangement to produce only one stereoisomer of 2 at the final stage of the photoreaction at room temperature.We also determined the effect of the oxygen-atom rearrangement on the rotational motion of the two crystallographibally independent Cp^* ligands (parallel and perpendicular arrangement). Using variable-temperature ^13C CP/MAS NMR and quadrupolar echo solid-state ^2H NMR spectroscopies, before photoirradiation, the activation energies for the rotation of the parallel and perpendicular Cp^* ligands in 1 were determined to be 30±3 and 10±1 kJ/mol, respectively, and after photoirradiation, in 2, they were much lower than those in 1 (20±2 and 8±1 kJ/mol, respectively). The large decrease in the activation energy for the parallel Cp^* in 2 is attributed to the relaxation of molecular stress via a stereospecific oxygen-atom rearrangement, which suggests that the rotational motion of the Cp^* ligands is coupled to the photochromism.Furthermore, we have found an absolute asymmetric photoisomerization of a new achiral photochromic dithionite complex having n-propyl moieties [(RhCp^<Pro>)_2(μ-CH_2)(μ-O_2SSO_2)] (Cp^<Pro>=η^5-C_5Me_4n-Propyl) in chiral crystals. This complex is crystallized in the space group of P2_12_12_1 and gives both crystals containing the helical isomers of P and M.We performed a crystalline-state photoreaction by using these chiral crystals in similar way to [(RhCp^*)_2(μ-CH_2)(μ-O_2SSO_2)] and obtained [RhCp^<Pro>)_2(μ-CH_2)(μ-OSOSO_2)] almost quantitatively. The obtained μ-OSOSO_2 complex has an e.e value of 95%.; 研究課題/領域番号:16350029, 研究期間(年度):2004 – 2007; 出典：「活性S-S結合による結晶相光応答錯体分子の構築と光機能の解明」研究成果報告書 課題番号16350029（KAKEN：科学研究費助成事業データベース（国立情報学研究所））（https://kaken.nii.ac.jp/ja/report/KAKENHI-PROJECT-16350029/163500292007kenkyu_seika_hokoku_gaiyo/)を加工して作成
• DOI: 10.24517/00063251
• Source: https://kanazawa-u.repo.nii.ac.jp/?action=repository_action_common_download&item_id=56977&item_no=1&attribute_id=26&file_no=1
• Access Restrictions: 限定公開
• Rights (production): CC BY-NC-ND
• Related Material: https://nrid.nii.ac.jp/ja/search/?kw=70101285; https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-16350029/; https://kaken.nii.ac.jp/ja/report/KAKENHI-PROJECT-16350029/163500292007kenkyu_seika_hokoku_gaiyo/
• Data Provider (Database): 国立情報学研究所 : 学術機関リポジトリデータベース（IRDB）（機関リポジトリ）; https://irdb.nii.ac.jp
• Original Data Provider (Database): 金沢大学 : 金沢大学学術情報リポジトリKURA