Related Experiment Video
Updated: Apr 27, 2026

Preparation of 6-aminocyclohepta-2,4-dien-1-one Derivatives via Tricarbonyltroponeiron
Published on: August 12, 2019
Stable 7,14-disubstituted-5,12-dithiapentacenes with quinoidal conjugation
Qun Ye1, Jingjing Chang, Xueliang Shi
1Department of Chemistry, National University of Singapore , 3 Science Drive 3, Singapore, 117543, Singapore.
Abstract:
Two 7,14-disubstituted-5,12-dithiapentacenes (1 and 2) with quinoidal conjugation were synthesized. Their ground-state quinoidal structures were proven by X-ray crystallographic analysis. They showed very different electronic and optical properties from those of the corresponding pentacene derivatives with diene conjugation, and their stability was significantly improved. Organic field effect transistors based on solution processed thin films of 1 and 2 exhibited a hole mobility of up to 0.032 cm(-2) V(-1) s(-1).
Related Concept Videos
Aromatic Hydrocarbon Cations: Structural Overview
Removing one hydrogen from the intervening CH2 group...
Stability of Conjugated Dienes
A comparison of the enthalpies of hydrogenation of dienes reveals that conjugated dienes release less heat on hydrogenation, rendering them more stable than their nonconjugated analogs.
Structure of Conjugated Dienes
Conjugated dienes are compounds characterized by the presence of alternating double and single bonds. In a conjugated system like 1,3-butadiene, the unhybridized 2p orbital on each carbon overlaps continuously, allowing the π electrons to be delocalized across the entire molecule. In contrast, this type of overlap does not occur in cumulated and isolated dienes, such as 2,3-pentadiene and 1,4-pentadiene, respectively. Instead, the π electrons remain localized between the...
Stability of Substituted Cyclohexanes
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
Disubstituted Cyclohexanes: cis-trans Isomerism
In cyclohexane, the substituents can occupy different positions generating distinct isomers....
![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)
