陽子結合電子移転による阻害された一次および二次アミンの電気化学合成

Dan Lehnherr¹, Yu-Hong Lam², Michael C Nicastri³

¹Process Research and Development , Merck & Co., Inc. , Rahway , New Jersey 07065 , United States.

Journal of the American Chemical Society

|December 19, 2019

まとめ

合成的に難しい阻害アミンは,新しい電気化学的方法によって入手できます. このアプローチでは,イミニウム塩と様々なシアノヘテロアーレンを利用し,アミンの合成における以前の制限を克服した.

科学分野:

有機化学
電気化学
合成方法論

背景:

ステリカルに阻害されたプライマリアミン,特にアルファから四次炭素へのアクセスは,重要な合成のハードルを提示します.
既存の方法は,これらの挑戦的なアミンモチーフを構築するための効率や広範な適用性が欠けていることが多い.

研究の目的:

阻害された原始アミンの合成のための新しい電気化学的戦略を開発する.
様々なイミニウム塩とシアノヘテロアーネスを用いて,この新しい方法の範囲と限界を調査する.

主な方法:

ベンチトップで安定したイミニウム塩とシアノヘテロアレン間の電気化学的クロスカップリング反応.
ピリジン,ピリミジン,ピラジン,ピューリン,アザインドールを含む様々な代替ヘテロサイクルを使用した.
密度関数理論 (DFT) の計算,サイクル電圧測定,および機械学的研究のためのNMRスペクトロスコーピーを使用した.

主要な成果:

簡単に入手できる原材料から,阻害された原始アミンを成功裏に合成した.
ヘテロサイクル (ハリド,CF3,エステル,アミド,エーテル,ヘテロサイクル,アルコール,アルキン) の多様な機能群を収容する,広範な基板の範囲を示した.
陽子結合電子移転とヘテロビラジカルクロスカップリングを含むメカニズムを提案した.

結論:

開発された電気化学的方法は,合成的に阻害されたアミンを効率的に提供します.
反応は幅広い機能群を許容し,複雑な分子合成における有用性を高める.
機械的調査は,新しい根基ベースのクロスカップリング経路を支持します.

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