含有aminotroponiminate连接体的阴阳基复合物
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
概括
合成和研究了带有N,N'-二异胺诺胺酸联体的阴阳复合物. 这些复合物表现出多样化的反应性,包括连接物转移,二元化和聚合催化,展示了它们在有机金属化学中的多功能性.
科学领域:
- 有机金属化学 有机金属化学
- 协调化学 协调化学
- 催化剂是一种催化剂.
背景情况:
- 复合物在催化和材料科学中至关重要.
- 该N,N'-二异烯胺胺酸联体为稳定反应性金属中心提供独特的固体和电子特性.
研究的目的:
- 为了合成和描述新型的含有N,N'-二异胺诺胺酸联体的阴阳性复合物.
- 研究这些复合物的与各种基质的反应性,并探索它们的催化应用.
主要方法:
- 前体的合成 ((i) Pr 2 -ATI) AlR 2 .
- 与电友性剂的反应,如[Ph(3) C][B(C(6) F(5)) 4) ]和B(C(6) F(5)) 3) 产生离子物种.
- 使用X射线晶体学,NMR光谱学和反应性研究进行表征.
- 在二分化和聚合反应中进行催化试验.
主要成果:
- 形成稳定的阴离子复合物,包括双核物种和无基复合物.
- 证明了连接体转移 (例如,C(6) F(5)(-)) 和基质协调 (MeCN,乙).
- 在三乙烯二聚化,氧化物聚合和甲基甲酸盐聚合过程中观察催化活性.
结论:
- 该N,N'-二异烯胺胺酸联体有效地稳定了cationic物种.
- 这些复合物表现出丰富的反应性,使得变化,如二分化和聚合.
- 这项研究强调了这些复合物的潜力,作为有机合成和聚合物科学中的催化剂.
相关概念视频
01:16Aldehydes 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.
01:07Acid 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...
01:19Structure 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...
01:25Basicity 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).
01:38Preparation 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.
01:07Amines: 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.