アミノトロポニミネートリガンドを含むカチオンアルミニウムアルキル複合体
A V Korolev1, E Ihara, I A Guzei
1Department of Chemistry, The University of Chicago, 5735 South Ellis Avenue, Chicago, IL 60637, USA.
Journal of the American Chemical Society
|August 23, 2001
まとめ
N,N'-二イソプロピラミノトロポニミネートリガンドを含むカチオンアルミニウム複合体を合成し,研究した. これらの複合体は,リガンド移転,二酸化,およびポリメリゼーション触媒を含む多様な反応性を表し,有機金属化学における多用途性を示しています.
科学分野:
- 有機金属化学 有機金属化学
- 協調化化学について
- カタリシス カタリシス カタリシス
背景:
- アルミニウム複合体は,触媒と材料科学において極めて重要です.
- N,N'-二イソプロピラミノトロポニミネートリガンドは,反応性金属の中心を安定させるためにユニークなステリックおよび電子特性を提供します.
研究 の 目的:
- N,N'-二イソプロピラミノトロポニミネートリガンドを特徴とする新しいカチオンのアルミニウム複合体を合成し,特徴づけること.
- これらの複合物の様々な基質との反応性を調査し,それらの触媒的応用を探求する.
主な方法:
- アルミニウム前駆物質の合成 ((i)Pr(2) -ATI)AlR(2).
- [Ph ((3) C][B (((C ((6) F ((5)) ((4))) とB (((C ((6) F ((5)) ((3))) のような電離性物質と反応して,カチオンの種を生成する.
- X線結晶学,NMRスペクトロスコピー,および反応性研究を用いた特徴付け.
- ディメリゼーションおよびポリメリゼーション反応における触媒試験.
主要な成果:
- 二核種と塩基のない複合体を含む安定したカチオンのアルミニウム複合体の形成.
- リンガンド移転 (C(6) F(5) 及び基板調整 (MeCN,アセトン) の実証.
- トートブチルアセチレン二酸化,プロピレン酸化物ポリメリゼーション,メチルメタクリlateポリメリゼーションにおける触媒活性の観察.
結論:
- N,N'-二イソプロピラミノトロポニミネートリガンドは,キャチオンのアルミニウム種を効果的に安定させます.
- これらの複合体は豊富な反応性を発揮し,二酸化およびポリメリ化などの変換を可能にします.
- この研究は,有機合成とポリマー科学における触媒としてのこれらのアルミニウム複合体の可能性を強調しています.
関連する概念動画
Aldehydes and Ketones with Amines: Imine and Enamine Formation Overview
Primary amines react with carbonyl compounds—aldehydes and ketones—to generate imines. Imines consist of a C=N double bond and are named Schiff bases after its discoverer—the German chemist Hugo Schiff. On the other hand, secondary amines react with carbonyl compounds to give enamines. In enamines, the presence of a C=C double bond adjacent to the nitrogen atom leads to the delocalization of the lone pair.
Acid Halides to Amides: Aminolysis
Aminolysis is a nucleophilic acyl substitution reaction, where ammonia or amines act as nucleophiles to give the substitution product. Acid halides react with ammonia, primary amines, and secondary amines to yield primary, secondary, and tertiary amides, respectively.
In the first step of the aminolysis mechanism, the amine attacks the carbonyl carbon of the acyl chloride to form a tetrahedral intermediate. In the second step, the carbonyl group is re-formed with the elimination of a chloride...
In the first step of the aminolysis mechanism, the amine attacks the carbonyl carbon of the acyl chloride to form a tetrahedral intermediate. In the second step, the carbonyl group is re-formed with the elimination of a chloride...
Structure of Amines
The hybridized nitrogen atom in amines possesses a lone pair of electrons and is bound to three substituents with a bond angle of around 108°, which is less than the tetrahedral angle of 109.5°. However, the C–N–H bond angle is slightly larger at 112°, with a carbon–nitrogen bond length of 147 pm. This carbon–nitrogen bond length of of amines is longer than the carbon–oxygen bond of alcohols (143 pm) but shorter than alkanes’ carbon–carbon bond (154 pm). These aspects are illustrated in Figure...
Basicity 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).
Preparation of Amines: Reductive Amination of Aldehydes and Ketones
Carbonyl compounds and primary amines undergo reductive amination first to produce imines, followed by secondary amines in the same reaction mixture, using selective reducing agents like sodium cyanoborohydride or sodium triacetoxyborohydride. Reductive amination produces different degrees of substitution of amines depending on the starting amine substrate.
Amines: Introduction
Amines are organic derivatives of ammonia. They are formed by replacing one or more ammonia protons with alkyl or aryl groups. Depending upon the number of organyl groups bonded to nitrogen, amines are classified as primary, secondary, or tertiary. Primary amines have one organyl group attached to the nitrogen atom, while secondary and tertiary amines have two and three organyl groups attached to the nitrogen atom, respectively.


