Direct Catalytic Asymmetric Cross-Aldol Reactions of Aliphatic Aldehydes

2020 Fiscal Year Final Research Report

• Project/Area Number: 18H02554
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 47010:Pharmaceutical chemistry and drug development sciences-related
• Research Institution: Kyoto Pharmaceutical University
• Principal Investigator: Furuta Takumi 京都薬科大学, 薬学部, 教授 (30336656)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 交差アルドール反応 / 触媒的不斉合成 / 軸性不斉 / アニリン / 基質認識

Outline of Final Research Achievements

The direct asymmetric cross-aldol reaction between the enolizable aliphatic aldehydes is still unrevealed and challenging problems in organic synthesis due to unavoidable generation of self-aldol and unwanted cross-aldol products. This cross-aldol reaction requires fine discrimination of the aldehyde substrates bearing similar reactivity by the catalyst. However, this type of substrate discrimination has not yet been achieved well. We examined the catalytic discrimination among the formyl groups of the aliphatic aldehydes by axially chiral aniline-type acid-base catalysts by virtue of their mild reactivities. This strategy worked well and realized highly cross-selective intermolecular cross-aldol reactions between enolizable alpha-oxy aldehyde and other aliphatic aldehydes in high stereoselectivities. Furthermore, the regio-, diastereo-, and enantioselective intramolecular cross-aldol reactions of enolizable aliphatic 1,7-diketones have been achieved.

Free Research Field

有機合成化学

Academic Significance and Societal Importance of the Research Achievements

本研究の課題である脂肪族アルデヒド間の触媒的かつ直接的な交差アルドール反応は、スタチン系医薬品など有用な医薬品の効率的合成に直結する、有用かつ環境負荷の少ない有機合成法である。しかし、その成就には、反応性が類似するアルデヒド間の触媒による識別が必須となる。穏やかな反応性を持つアニリン性酸塩基触媒でこの基質識別を達成した本研究は、「触媒による基質識別に基づく選択的分子変換」の端緒を開く学術的価値を有する。さらに、医薬品など有用物質の効率的な合成に直結する社会的な意義も持つ。