酒精的pKa决定了它们与减少的替代的硫基聚的反应性
Kamaless Patra1, William W Brennessel1, Ellen M Matson1
1Department of Chemistry, University of Rochester, Rochester, NY, 14627, USA. matson@chem.rochester.edu.
Dalton transactions (Cambridge, England : 2003)
|November 26, 2024
概括
替代的硫基聚合物激活了酒精中的OH键,形成了氧化物种. 酒精酸度 (pKa) 影响了反应机制,影响了-联体相互作用.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
- 化学 的化学
背景情况:
- 替代的聚基聚作为单个原子在硫化物表面 (U@MoS2) 的模型.
- 了解OH键激活对于催化过程至关重要.
研究的目的:
- 为了研究由替代的硫基聚合物激活各种酒精的OH键激活.
- 确定酒精pKa对反应机制的影响.
主要方法:
- (Cp*3Mo3S4) UCp*与不同的酒精 (甲醇,,2,6-二二,非-三-丁醇,三-butanol) 的反应.
- 由此产生的氧化物种的表征.
- 独立合成特定的氧化物产品.
主要成果:
- 单氧化物种 (Cp*3Mo3S4) Cp*U(OR) 由具有不同pKa值的酒精形成.
- 丁醇诱导的Cp*连接体的质子分解,产生 (Cp*3Mo3S4) U(OtBu) 3.
- 绝缘阻碍被排除为不同反应性的原因.
结论:
- 酒精的-OH质子的pKa是指导OH键激活机制的关键因素.
- 这项研究扩大了对聚酸聚中中心O-H键激活的理解.
相关概念视频
Acidity and Basicity of Alcohols and Phenols
18.6K
Like water, alcohols are weak acids and bases. This is attributed to the polarization of the O–H bond making the hydrogen partially positive. Moreover, the electron pairs on the oxygen atom of alcohol make it both basic and nucleophilic. Protonation of an alcohol converts hydroxide, a poor leaving group, into water—a good one. The two acid–base equilibria corresponding to ethanol are depicted below.
18.6K
Protection of Alcohols
7.2K
This lesson delves into the concept of protection and deprotection of a functional group fundamental to synthetic organic chemistry. These phenomena are explained in the context of aliphatic and aromatic alcohols.
Protection
It defines a protecting group as the masking agent to make the more reactive species inert to a given set of conditions. This concept is depicted via the illustration of liquid flow through different outlets in an assembly of pipes. The analogy helps to understand the role...
Protection
It defines a protecting group as the masking agent to make the more reactive species inert to a given set of conditions. This concept is depicted via the illustration of liquid flow through different outlets in an assembly of pipes. The analogy helps to understand the role...
7.2K
Conversion of Alcohols to Alkyl Halides
7.1K
This lesson delves into the conversion of alcohols to corresponding alkyl halides and the mechanism of action for different reagents. Typically, the hydroxyl group is first protonated to convert it to a stable leaving group. Consequently, based on the starting alcohol, the mechanism undergoes either of the nucleophilic substitution routes, SN1 or SN2. Tertiary alkyl halides are made using the two-step SN1 mechanism that occurs via a carbocation intermediate, which is stabilized by...
7.1K
Radical Oxidation of Allylic and Benzylic Alcohols
1.9K
Activated manganese(IV) oxide can selectively oxidize allylic and benzylic alcohols via a radical intermediate mechanism. Primary allylic alcohols are oxidized to aldehydes, while secondary allylic alcohols yield ketones. The redox reaction of potassium permanganate with an Mn(II) salt such as manganese sulfate (under either alkaline or acidic conditions), followed by thorough drying, yields the oxidizing agent: activated MnO2. While MnO2 is insoluble in the solvents used for the reaction, the...
1.9K
Alcohols from Carbonyl Compounds: Reduction
10.2K
Reduction is a simple strategy to convert a carbonyl group to a hydroxyl group. The three major pathways to reduce carbonyls to alcohols are catalytic hydrogenation, hydride reduction, and borane reduction.
Catalytic hydrogenation is similar to the reduction of an alkene or alkyne by adding H2 across the pi bond in the presence of transition metal catalysts like Raney Ni, Pd–C, Pt, or Ru. Aldehydes and ketones can be reduced by this method, often under mild to moderate heat (25–100°C) and...
Catalytic hydrogenation is similar to the reduction of an alkene or alkyne by adding H2 across the pi bond in the presence of transition metal catalysts like Raney Ni, Pd–C, Pt, or Ru. Aldehydes and ketones can be reduced by this method, often under mild to moderate heat (25–100°C) and...
10.2K
Oxidation of Alcohols
12.8K
In this lesson, the oxidation of alcohols is discussed in depth. The various reagents used for oxidation of primary and secondary alcohols are detailed, and their mechanism of action is provided.
The process of oxidation in a chemical reaction is observed in any of the three forms:
The process of oxidation in a chemical reaction is observed in any of the three forms:
12.8K


