在小硫胺基中道化原子:N-甲基硫尿素,硫胺基和2-乙胺基
Hanna Rostkowska1, Leszek Lapinski1, Maciej J Nowak1
1Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw, Poland.
概括
分离了氨酸衍生物的稳定离子分离体. 在紫外线照射后,高能醇分离体形成,其中一些经历了自发的原子道回归到子形式.
科学领域:
- 物理化学 物理化学
- 频谱学是一种光谱学.
- 化学物理 化学物理
背景情况:
- 离子-离子复合是一种基本的化学过程.
- 在有机化学中,了解体的稳定性和转变是至关重要的.
- 低温矩阵隔离提供了一个独特的环境来研究反应性中间体.
研究的目的:
- 为了研究N-甲基尿素,硫胺和2-酸胺的平衡性平衡.
- 在孤立的条件下研究离子和离子 tautomers 之间的相互转换.
- 探索原子道化在分体转换中的作用.
主要方法:
- 在低温的子矩阵中隔离子 tautomers.
- 使用紫外线照射 (λ>270 nm) 进行醇分离体的光生成.
- 在3.5K时对矩阵分离化合物的光谱分析.
主要成果:
- 成功地分离了N-甲基尿素,硫胺和2-氨酸胺的稳定离子分离体.
- 紫外线照射产生了更高能量的醇分离体.
- N-甲基尿urea 和 thiobenzamide thiols 经历了自发的 thiol → thione 原子道化,这取决于 imino 的方向.
- 2-cyanothioacetamide thiol异构体没有显示 thiol → thione 转换,只有 S-H 旋转体的形状变化.
结论:
- 伊米诺原子的方向决定了醇 → 离子原子道的可行性.
- 与N-甲基urea和thiobenzamide相比,2-cyanothioacetamide表现出明显的复合体行为.
- 矩阵隔离对于研究微妙的分体动力学和道现象是有效的.
相关概念视频
02:26Preparation and Reactions of Sulfides
4.8K
Sulfides are the sulfur analog of ethers, just as thiols are the sulfur analog of alcohol. Like ethers, sulfides also consist of two hydrocarbon groups bonded to the central sulfur atom. Depending upon the type of groups present, sulfides can be symmetrical or asymmetrical. Symmetrical sulfides can be prepared via an SN2 reaction between 2 equivalents of an alkyl halide and one equivalent of sodium sulfide.
4.8K
02:33Preparation and Reactions of Thiols
6.2K
Thiols are prepared using the hydrosulfide anion as a nucleophile in a nucleophilic substitution reaction with alkyl halides. For instance, bromobutane reacts with sodium hydrosulfide to give butanethiol.
6.2K
01:28Preparation 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
01:26Radical Substitution: Hydrogenolysis of Alkyl Halides with Tributyltin Hydride
1.8K
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The bonds formed in this reaction are stronger than the bonds broken, making it energetically favorable. The reaction follows a radical chain mechanism similar to radical halogenation...
The bonds formed in this reaction are stronger than the bonds broken, making it energetically favorable. The reaction follows a radical chain mechanism similar to radical halogenation...
1.8K
01:07Acid Halides to Amides: Aminolysis
2.7K
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...
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2.7K
01:19Diazonium Group Substitution: –OH and –H
2.8K
Nitrous acid, a weak acid, is prepared in situ via the reaction of sodium nitrite with a strong acid under cold conditions. This nitrous acid prepared in situ reacts with primary arylamines to form arenediazonium salts. Such reactions are known as diazotization reactions. As shown in Figure 1, the formation of arenediazonium salts begins with the decomposition of nitrous acid in an acidic solution to give nitrosonium ions.
2.8K