JoVE - Journal of Visualized Experiments
JoVE Visualize
Contact Us
这页已由机器翻译。其他页面可能仍然显示为英文。 View in English

通过四碳酸催化组合的野生运行 (C) 功能化/应对重新安排景观:过渡后状态动态不匹配是否影响产品分布?

  • 0Department of Chemistry, University of California, Davis, Davis, California 95616, United States.
Journal of the American Chemical Society +

|

2024年二月28日

在PubMed上查看摘要

概括

此摘要是机器生成的。

相关概念视频

[3,3] Sigmatropic Rearrangement of 1,5-Dienes: Cope Rearrangement 01:21

2.7K

The Cope rearrangement is classified as a [3,3] sigmatropic shift in 1,5-dienes, leading to a more stable, isomeric 1,5-diene. The reaction involves a concerted movement of six electrons, four from two π bonds and two from a σ bond, via an energetically favorable chair-like transition state.

From a molecular orbital perspective, the rearrangement can be viewed as the interaction between the ground state frontier orbitals of the allyl anion and cation. Under thermal conditions, the...

[3,3] Sigmatropic Rearrangement of Allyl Vinyl Ethers: Claisen Rearrangement 01:24

2.1K

The Claisen rearrangement is a [3,3] sigmatropic rearrangement of allyl vinyl ethers to unsaturated carbonyl compounds. The rearrangement is a concerted pericyclic reaction proceeding via a chair-like transition state.

An aromatic Claisen rearrangement involves the conversion of allyl aryl ethers to an unstable ketone intermediate, which tautomerizes to give ortho-substituted phenols.

However, ortho-substituted allyl aryl ethers exclusively yield para-substituted phenols via two sequential...

Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry 01:29

4.6K

Diels–Alder reactions between cyclic dienes locked in an s-cis configuration and dienophiles yield bridged bicyclic products.

Dienophiles with one or more electron-withdrawing substituents form stereochemically different products in which the substituents are oriented in an endo (towards) or exo (away) configuration relative to the double bond.

The endo isomer is formed faster and is the kinetic product. The exo isomer is more stable and is the thermodynamic...

Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration 02:34

8.4K

The rate of acid-catalyzed hydration of alkenes depends on the alkene's structure, as the presence of alkyl substituents at the double bond can significantly influence the rate.

The reaction proceeds with the slow protonation of an alkene by a hydronium ion to form a carbocation, which is the rate-determining step.
The reaction involving a tertiary carbocation intermediate is faster than a reaction proceeding through a secondary or primary carbocation. This can be justified by comparing their...

Regioselectivity and Stereochemistry of Hydroboration 02:36

8.1K

A significant aspect of hydroboration–oxidation is the regio- and stereochemical outcome of the reaction.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn...

[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction 01:16

10.2K

The Diels–Alder reaction is an example of a thermal pericyclic reaction between a conjugated diene and an alkene or alkyne, commonly referred to as a dienophile. The reaction involves a concerted movement of six π electrons, four from the diene and two from the dienophile, forming an unsaturated six-membered ring. As a result, these reactions are classified as [4+2] cycloadditions.

From a molecular orbital perspective, the interacting lobes of the two π systems must be in phase...