(ヘテロ) アレンのメタ-選択的C-H放射性化のための連続的なIr/Cu媒介法
Jay S Wright1, Liam S Sharninghausen2, Sean Preshlock1
1Department of Radiology, University of Michigan, Ann Arbor, Michigan 48109, United States.
Journal of the American Chemical Society
|April 29, 2021
まとめ
この研究は,連続的なイリジウム/銅触媒を用いたアレンのメタ選択的C-H放射性化のための新しいベンチトップ方法を示している. このプロセスは,中間物質を分離することなく,効率的にフッ素18ラベル付アレンを生成し,放射性トレーサーの合成を簡素化します.
科学分野:
- 有機化学
- 放射化学
- カタリシス
背景:
- 有機分子にフッ素-18 (18F) を導入するための効率的な方法の開発は,ポジートロン放出トモグラフィー (PET) 画像処理に不可欠です.
- 現在の放射性化技術は,しばしば特殊な設備と多段階の手順を必要とし,アクセシビリティを制限します.
- メタ選択的C-H機能化は特定の同位体への直接的な経路を提供しているが,放射性化によってこれを達成することは依然として困難である.
研究 の 目的:
- (ヘテロ) アレンのメタセレクティブC-H放射性化のための新しい,ベンチ・トップ対応のシーケンシャル・イリジウム/銅媒介プロセスの開発.
- フッ素18を標識した (ヘテロ) アレンの高収量と純度を,簡素化された"ポット"手順で達成する.
- このプロセスの自動化を実証するために,PETイメージング剤を合成します.
主な方法:
- (ヘテロアレン) 基質の連続したIr-触媒化C ((sp2) -Hボリレーションにより,オルガノボロナートエステルが形成される.
- [18F]テトラブチルアモニアム・フッ化物を用いて,中間オルガノボロナートの直接銅媒介放射性化.
- シュレンクやグローブボックスを使わずにベンチ上で実行し,中間隔離を避けます.
主要な成果:
- 1,3-ジメトキシベンゼンとメタチロシン誘導体のC-H放射性化に成功しました.
- [18F]1-フッ素-3,5-ジメトキシベンゼンは,分離された放射化学的収量で37 ± 5%で,放射化学的純度>99%で得られた.
- 18Fで標識されたメタチロシン誘導体は,25%の分離放射化学的収量,99%の放射化学的純度,および0.52Ci/μmolのモラー活性で得られた.
- プロセスはTracerLab FXFNモジュールで自動化されています.
結論:
- 開発された連続的なIr/Cu媒介プロセスは,メタ選択的C-H放射性化のための効率的でアクセシブルな方法を提供します.
- ベンチトップ,単一ポット性質の反応は,F-ラベル付き化合物の合成を簡素化します.
- この方法は,PETイメージングのための新しい放射性トレーサーのルーチン合成に希望があります.
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