1,2,3-トライアジン1-オキシドへの核愛添加におけるサイト逆転
Luca De Angelis1, Graham C Haug1, Gildardo Rivera2
1Department of Chemistry, The University of Texas at San Antonio, San Antonio, Texas 78249, United States.
Journal of the American Chemical Society
|June 9, 2023
まとめ
この研究では,1,2,3-トリアジンおよびその1酸化物誘導体への核性添加を調査し,反応部位を区別する. 合成化学を助長する様々なヌクレオフィルの地域選択性と反応条件を明らかにする.
科学分野:
- 有機化学
- ヘテロサイクル化学
- 合成方法論
背景:
- 逆電子需要ダイエルス-アルダー (IEDDA) サイクル添加は1,2,3-トリアジンにとって重要な反応である.
- 1,2,3-トリアジンへの核性添加は知られているが,地域選択性に関する包括的な理解がない.
- トリアジン核 (C-4対C-6) への核性攻撃の好ましい場所は未調査のままである.
研究 の 目的:
- 1,2,3-トリアジンと1,2,3-トリアジン-1-オキシドのフレームワークの核性添加部位を調査し,区別する.
- これらのヘテロサイクルのシステムとの様々なヌクレオフィル (C-, N-, H-, O-, S-) の反応性を探求する.
- これらの反応における地域選択性に影響を与える要因を解明する.
主な方法:
- 非対称な1,2,3-トリアジン-1-酸化物とその脱酸素化対称物の合成
- これらのトリアジン系が,カルバニオン,アミン,水素,アルコキシド,およびチオールを含む多様な核性物質と反応する.
- 反応メカニズム,地域選択性,およびステリックおよび電子的要因の影響を分析するために計算研究を使用した.
主要な成果:
- C-およびN-ヌクレオフィルは,トリアジンおよびトリアジン-1-酸化物系の両方で,優先的にC-6位置に添加され,トリアジン-1-酸化物系ではより迅速な産物形成が観察される.
- O核愛素 (アルコキシド) は,トリアジン-1-オキシドのC-4位置に対して高い選択性を示す.
- S-核性および水素は,軽度な機能群耐性条件下で,トリアジンに対するC-6およびトリアジン-1-酸化物に対するC-4で,異なる地域選択性を示す.
結論:
- この研究は,1,2,3-トリアジンおよび1,2,3-トリアジン-1-オキシード・スキャフォードにおける核愛添加領域選択性の包括的な理解を提供します.
- この研究は,核愛者とトリアジンの酸化状態に基づいて反応部位を区別する能力を強調しています.
- この発見は1,2,3-トリアジン誘導体を含む合成戦略の合理的な設計のための貴重な洞察を提供します.
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