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高電子リッチゼロバルントグループ10ディボラベンゼンポゴスティック複合体の合成と反応性

Maximilian Dietz^1,2, Merle Arrowsmith^1,2, Lukas Endres^1,2

¹Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland 97074, Würzburg, Germany.

Journal of the American Chemical Society

|October 2, 2023

まとめ

サイクルアルキル (アミノ) カーベンの安定化により,1,4-ジボラベンゼンは新しいニッケル,パラジウム,プラチナ複合体を形成する. これらの複合体は,金属のみのルイスペアとPt (II) スタニル水素の形成を含むユニークな電子特性と反応性を表しています.

科学分野:

有機金属化学
協調化学
材料科学

背景:

1,4-ジボラベンゼン (DBB) は,調節可能な電子特性を持つユニークなリガンドである.
グループ10の金属 (Ni,Pd,Pt) は,触媒と材料科学において極めて重要です.
サイクルアルキルアミノカルベン (CAAC) は強力なシグマドナーであり,効果的な安定化リガンドである.

研究の目的:

CAAC-DBBリガンドで安定した新型ゼロバレントグループ10の金属複合体を合成し,特徴づけること.
これらの新しい有機金属化合物の電子特性と反応性を調査する.
メタルのみのルイスペア (MOLP) と他の派生複合体の形成を調査する.

主な方法:

金属前駆体 ([Ni(CO) 4 , [M(nbe) 2) との反応によるDBB金属複合体の合成.
IRスペクトル,X線結晶,UV-Vis-NIRスペクトルを用いた特徴付け.
電子トランジションとスピン軌道結合 (SOC) を理解するために,時間依存密度関数理論 (TD-DFT) を用いた計算研究.

主要な成果:

[η6-DBB (Ni) ] (2) と [η6-DBB (M) ] (3-M,M=Pd,Pt) の複合体の分離
DBBリガンドは強力なπドナー特性を示し,金属センターの電子系に影響を与えます.
PdとPt複合体は,金属中心の電子移行に起因する強力な近赤外線吸収を示している.
Fe(CO) 5との反応により,二重COブリッジM(0)→Fe(0) のMOLP (4-M) が得られます.
Pt複合体は,Pt (II) スタニル水素を形成するために酸化Sn-Hを加える.

結論:

CAAC-DBBは,低値グループ10の金属を安定させるための多機能リガンドです.
これらの複合体の電子構造が光学および反応性特性を決定する.
この研究は,新しい金属のみのルイスペアと機能化された有機金属複合体への経路を示しています.

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