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(+) ワイホエンセンの非対称的全合成

Yongzheng Qu¹, Zheyuan Wang¹, Zhongchao Zhang¹

¹Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, 518055, China.

Journal of the American Chemical Society

|March 24, 2020

まとめ

この研究では,独特の四環原子核を持つ複雑な分子である (+) -ワイホエンセンの最初の非対称的全合成が詳細に示されています. 合成には,触媒添加と急性水素原子移転を含む一連のステレオ選択反応が用いられました.

科学分野:

有機化学
合成化学
自然製品合成

背景:

分子 (+) -ワイホエンセンは複雑なシス融合 [6,5,5,5] テトラサイクルの構造を有する.
この構造には角形のトリキナンのモチーフと4つの隣接する四次炭素原子が含まれ,重要な合成課題を提示します.

研究の目的:

(+) ワイホエンセンの最初の非対称的全合成を達成する.
この複雑な天然製品へのステレオ化学的に制御された合成経路を開発する

主な方法:

銅で触媒化された非対称結合体1,4添加物
ディアステレオセレクティブコニアエネ反応
ダイアステロセレクティブ分子内パウソン・カンド反応
ニッケル触媒によるダイアステレオセレクティブ結合体 1,4-添加.
ラジカルが誘発する分子内水素原子移転 (HAT).

主要な成果:

(+) ワイホエンセンのシス融合 [6,5,5,5] テトラサイクルの核の成功.
合成シーケンス全体でステレオ化学的制御が維持された.
制御実験とDFT計算により,提案されたHATメカニズムが検証されました.

結論:

開発された合成戦略は, (+) ワイホエンセンの効率的な経路を提供する.
この研究は,複雑な分子合成における触媒的非対称反応とHATの有用性を強調しています.

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