融合核性および水素結合触媒:アニオン結合によるアミンの運動解離へのアプローチ
Chandra Kanta De1, Eric G Klauber, Daniel Seidel
1Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA.
Journal of the American Chemical Society
|November 26, 2009
まとめ
チラルアシルピリジニウム塩は,非対称な核好性触媒を可能にします. この新しいアプローチは,キラル型チオウレアアニオン受容体を使用して,動的アミン混合物を効果的に解消します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- アシンメトリック・シンセシス
背景:
- 核性触媒は有機合成において極めて重要です.
- これらの反応でエナチオセレクティブ性を達成することは,依然として課題です.
- 4-(ジメチラミノ) ピリジン (DMAP) は,一般的な核愛性触媒である.
研究 の 目的:
- 非対称な核愛性触媒の新概念を導入する.
- エナチオセレクティブ変換のためのキラルアシルピリジニウム塩を開発する.
- このシステムの実用性を動的解像度で示すために.
主な方法:
- DMAPとベンゾ酸アンヒドリドからアシルピリジニウム塩を合成する.
- キラルチオウレアアニオン受容体を用いたキラル誘導.
- アミンの運動解像度における応用.
主要な成果:
- キラルアシルピリジニウム塩を成功裏に生成しました.
- アニオン受容体相互作用による効果的な非対称誘導が実証されています.
- 高い効率でアミンの運動解像度を達成しました.
結論:
- 提出されたコンセプトは,非対称な核愛性触媒の新しい戦略を提供します.
- チラルアシルピリジニウム塩は,エナンチオセレクティブ反応の有効な触媒である.
- この方法は,動的アミン解像度のための強力なツールを提供します.
関連する概念動画
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The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
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01:25Basicity of Heterocyclic Aromatic Amines
Heterocyclic amines, where the N atom is a part of an alicyclic system, are similar in basicity to alkylamines. Interestingly, the heterocyclic amine having a nitrogen atom as part of an aromatic ring has much less basicity than its corresponding alicyclic counterpart. For this reason, as presented in Figure 1, piperidine (pKb = 2.8) is significantly more basic than pyridine (pKb = 8.8).
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02:34Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
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