強いアリファティックC−H結合の直接アリレーション
Ian B Perry1, Thomas F Brewer1, Patrick J Sarver1
1Merck Center for Catalysis at Princeton University, Princeton, NJ, USA.
Nature
|August 3, 2018
まとめ
この研究は,直接のC ((sp3) アリレーションのための新しい二次触媒方法を導入する. 豊富なC−H結合をアリルブロミドと効率的に結合し,温和な条件下で貴重なC−sp3−C−sp2結合を生成する.
科学分野:
- 有機化学
- キャタリシス
- 合成方法論
背景:
- 移行金属触媒は,sp3-ハイブリッド化された炭素原子の機能化に制限があります.
- 直接のC−H結合の機能化は理想的だが,強い中性C−sp3−H結合には困難である.
- 既存の方法はしばしば機能化された基板または厳しい条件を必要とします.
研究 の 目的:
- アリファティックC−H結合の直接C−sp3アリレーションのための軽度かつ一般的なプロトコルを開発する.
- 簡単に手に入る材料を使って,C ((sp3) -C ((sp2)) の結合を形成できるようにする.
- 複雑で医学的に重要な分子に 新しい合成経路を提供するために
主な方法:
- ライト駆動水素原子移転 (HAT) とニッケル触媒を組み合わせた二重触媒システム.
- ポリオックスメタラート光触媒は,強い中性C-H結合から炭素中心のラジカルを生成するためにHATを容易にします.
- ニッケル触媒はこれらのラジカルとアリルブロミドの交互結合を媒介する.
主要な成果:
- 様々なアリファティック・フレームワークのC ((sp3)) の直接結合を成功させた.
- 温和な条件下でC ((sp3) -C ((sp2) のクロスカップリングされた製品の形成
- 自然産物と化学原料に適用可能なことが実証されています.
結論:
- 開発されたプロトコルは 複雑な分子への前例のない 一段階のアクセスを提供します
- この方法は,sp3-ハイブリッド化された炭素における伝統的なクロスカップリング反応の限界を克服する.
- この技術により,以前は反応性のない場所での機能化が可能になり,合成の可能性が広がります.
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A titration is carried out for 25.00 mL of 0.100 M HCl (strong acid) with 0.100 M of a strong base NaOH. The pH at different volumes of added base solution can be calculated as follows:
(a) Titrant volume = 0 mL. The solution pH is due to the acid ionization of HCl. Because this is a strong acid, the ionization is complete and the hydronium ion molarity is 0.100 M. The pH of the solution is then:
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