ターミナルオレフィンの触媒制御C-O対C-Nアリル機能化
Iulia I Strambeanu1, M Christina White
1Roger Adams Laboratory, Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
Journal of the American Chemical Society
|July 17, 2013
まとめ
研究者は,単純なオレフィンから貴重な化学前駆物質を合成するための新しいパラジウム触媒法を開発しました. この触媒系は,アミノアルコールやダイアミンの合成が異なることを可能にし,化学薬品の生産に柔軟性をもたらします.
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
- 合成方法論 合成方法論
背景:
- 複雑な有機分子を合成するには,多くの場合,多段階のプロセスが必要です.
- 先駆体合成のための効率的な触媒方法の開発は,効率的な化学製品生産に不可欠です.
研究 の 目的:
- 末端オレフィンからシン-1,2-アミノアルコールとシン-1,2-ダイアミン前駆体の異なる合成を達成するために.
- 制御された合成のためのルイス酸コカタリシスによる新しいパラジウム (((II)) 触媒システムを調査する.
主な方法:
- ルイス酸コカタリシスと組み合わせたパラジウム ((II) カタリシスを利用した.
- アンチ-2-アミノオクサゾリンの合成のために,シルバートリフラートを使ったパラジウム (II) /ビス-スルフォキシドの触媒を用いる.
- 抗イミダゾリジノン製品にアクセスするために,ビス-スルフォキシドリガンドを除去することによって,触媒システムを修正しました.
主要な成果:
- パラジウム (II) /ビス-硫酸化物触媒を用いて,良好から優れた収量で,抗-2-アミノオキサゾリン (C-O) の最初の合成を達成しました.
- リガンド除去時に反応性の完全な切り替えが示され,良好な収量と高いダイアステロ選択性を持つ抗イミダゾリジノン製品 (C-N) が得られました.
- 機械学的研究により,アルリルC-H分裂/機能化からオレフィンイソメリゼーション/酸化アミネーションへの切り替えが明らかになった.
結論:
- 価値ある前駆物質の分散合成のための汎用的なパラジウム触媒方式を確立した.
- 触媒システムは,調節可能な反応性を提供し,共通の出発材料から異なる化学的支架へのアクセスを可能にします.
- この発見は,パラジウム触媒の反応機構の制御に関する新しい洞察を提供します.
関連する概念動画
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Introduction
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01:21Acid-Catalyzed α-Halogenation of Aldehydes and Ketones
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The hydrogenation process takes place on the surface of...
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Introduction
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A significant aspect of hydroboration–oxidation is the regio- and stereochemical outcome of the reaction.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
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