相关实验视频
Updated: Jun 3, 2025

08:04
Preparation of Functional Silica Using a Bioinspired Method
Published on: August 1, 2018
17.1K
通过有机氨基具有多样结构的有机氨基合成异型二氧化纳米粒子
Yuanqing Fan1, Lili Wei2, Libin Kang3
1School of Chemical Science and Engineering, Tongji University, Shanghai, People's Republic of China.
Nanotechnology
|January 9, 2025
概括
具有特定结构的有机胺控制了二氧化纳米粒子形状. 较长链的二胺和线性三胺产生异型纳米粒子 (AISNPs),而其他形成异型纳米粒子 (ISNPs).
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 化学 化学 化学
背景情况:
- 控制纳米粒子形态对于先进的材料应用至关重要.
- 纳米粒子 (NP) 是多功能性的,但通常以同位素形式合成.
- 了解有机修饰剂在NP合成中的作用是关键.
研究的目的:
- 研究有机氨基结构对二氧化纳米粒子形态学的影响.
- 使用量身定制的有机氨基酸合成异型氧化纳米粒子 (AISNPs).
- 阐明控制异构性与异构性纳米颗粒 (ISNPs) 形成的机制.
主要方法:
- 使用各种有机胺 (单胺,二胺,三胺,四胺) 合成二氧化纳米颗粒.
- 纳米粒子形态的表征 (异极性与异极性).
- 氨基结构的分析,包括氨基基团的链长和空间排列.
主要成果:
- 单胺和短链二胺 (<4 Å) 导致同位素纳米粒子 (ISNPs).
- 具有较长链长 (>4 Å) 的二胺和线性三胺产生了异型纳米颗粒 (AISNPs).
- 非线性三胺和状四胺也指导了ISNP的形成.
结论:
- 氨基组之间的距离和它们在有机氨基中的空间排列是指导纳米粒子合成的关键因素.
- 当有机氨基连接多个初级粒子时,AISNP会形成,这需要特定的氨基几何和距离.
- 由于分子内相互作用或防止粒子桥接的固体障碍,ISNP形成.
相关概念视频
Structure of Amines
2.4K
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’...
2.4K
Preparation of 1° Amines: Azide Synthesis
3.8K
Direct alkylation of ammonia produces polyalkylated amines, along with a quaternary ammonium salt. To exclusively prepare primary amines, the azide synthesis method can be used.
Azide ions act as good nucleophiles and react with unhindered alkyl halides to form alkyl azides. Alkyl azides do not participate in further nucleophilic substitution reactions, thereby eliminating the chances of polyalkylated products. Alkyl azides are reduced by hydride-based reducing agents, like lithium aluminum...
Azide ions act as good nucleophiles and react with unhindered alkyl halides to form alkyl azides. Alkyl azides do not participate in further nucleophilic substitution reactions, thereby eliminating the chances of polyalkylated products. Alkyl azides are reduced by hydride-based reducing agents, like lithium aluminum...
3.8K
Preparation of Amides
3.0K
Amides are synthesized by treating carboxylic acids with amines in the presence of dehydrating agents like dicyclohexylcarbodiimide (DCC).
The DCC-promoted synthesis of amides begins with the protonation of DCC by carboxylic acid. The protonation makes it a better acceptor. Next, the addition of carboxylate to the protonated carbodiimide gives a reactive acylating agent.
Subsequently, the amine acts as a nucleophile that attacks the acylating agent to form a tetrahedral intermediate. In the...
The DCC-promoted synthesis of amides begins with the protonation of DCC by carboxylic acid. The protonation makes it a better acceptor. Next, the addition of carboxylate to the protonated carbodiimide gives a reactive acylating agent.
Subsequently, the amine acts as a nucleophile that attacks the acylating agent to form a tetrahedral intermediate. In the...
3.0K
Preparation of 1° Amines: Gabriel Synthesis
3.5K
Direct alkylation is not a suitable method for synthesizing amines because it produces polyalkylated products. Gabriel synthesis is the most preferred method to exclusively make primary amines. The method uses phthalimide, which contains a protected form of nitrogen that participates in alkylation only once to predominantly give primary amines.
Strong bases like NaOH or KOH deprotonate the phthalimide to form the corresponding anion, which acts as a nucleophile. Further, the anion attacks an...
Strong bases like NaOH or KOH deprotonate the phthalimide to form the corresponding anion, which acts as a nucleophile. Further, the anion attacks an...
3.5K
Preparation of Amines: Alkylation of Ammonia and Amines
3.2K
Alkylation is one of the methods used to prepare amines. Direct alkylation of ammonia or a primary amine with an alkyl halide gives polyalkylated amines along with a quaternary ammonium salt through successive SN2 reactions. This process of making the quaternary salt through the direct alkylation method is called exhaustive alkylation.
Each alkylation step makes the nitrogen center more nucleophilic, which triggers successive alkylations until a quaternary ammonium salt is formed. Considering...
Each alkylation step makes the nitrogen center more nucleophilic, which triggers successive alkylations until a quaternary ammonium salt is formed. Considering...
3.2K
Nomenclature of Aryl and Heterocyclic Amines
2.3K
The simplest aromatic amine is phenylamine, which contains an –NH2 functionality directly attached to an aromatic ring. The name aniline is designated for this skeleton. As shown in Figure 1, the common names of the functionalized anilines involve prefixes ortho-, meta-, and para- to indicate the substitution position. Different functionalized aniline derivatives also have notable trivial names.
2.3K

