Related Experiment Video
Updated: Aug 13, 2025
10:44
Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
10.9K
Global Search for Stable C4H5NO Compounds-Guinness Molecules and Stability Islands
Oleg A Mikhaylov1, Ilya D Gridnev1
1N. D. Zelinsky Institute of Organic Chemistry, Leninsky Prosp. 47, 119991 Moscow, Russia.
Molecules (Basel, Switzerland)
|January 21, 2023
Summary
Global reaction route mapping identified "Guinness molecules" and over 150 stable structures for C4H5NO. These compounds form a "Stability Island," indicating similar functionalities share a narrow free energy range.
Area of Science:
- Computational chemistry and theoretical organic chemistry.
- Investigating reaction pathways and molecular stability.
Background:
- Understanding the diverse structures and stability of small organic molecules is crucial.
- Computational methods are essential for exploring vast chemical spaces.
Purpose of the Study:
- To comprehensively map reaction routes for C4H5NO isomers.
- To identify and characterize stable molecular structures, including novel ones.
Main Methods:
- Utilizing Global Reaction Route Mapping (GRRM) analysis.
- Calculating free energies of formation for identified stable minima.
Main Results:
- Discovery of two specific "Guinness molecules" (000 and 001) within the C4H5NO composition.
- Identification of approximately 150 additional stable minima for C4H5NO.
- Observation that compounds with similar functionalities cluster within a limited free energy range, forming a "Stability Island".
Conclusions:
- The C4H5NO chemical space contains a significant number of stable isomers.
- "Guinness molecules" represent specific stable configurations within this space.
- The "Stability Island" concept provides a framework for understanding the energetic landscape of related chemical compounds.
Keywords:
Guinness moleculesN-O heterocyclescyanoketonesisonitrilesrelative stabilitiessinglet carbenesMore Related Videos
Related Concept Videos
02:30Stability of Substituted Cyclohexanes
12.8K
This lesson discusses the stability of substituted cyclohexanes with a focus on energies of various conformers and the effect of 1,3-diaxial interactions.
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...
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...
12.8K
01:28Structures of Carboxylic Acid Derivatives
2.8K
Structure of Carboxylic Acid Derivatives
Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the...
Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the...
2.8K
01:19Types of Enols and Enolates
2.8K
Aldehydes and ketones form enols, although only about 1% of the enol is present at the equilibrium for simple monocarbonyl compounds. The enol form is undetectable for acetaldehyde, present as only 1.5 × 10−4 % of acetone, and present as only 1.2% of cyclohexanone. Two kinds of regioisomeric enols are possible for unsymmetrical ketones, and their net composition is 1% at equilibrium. This instability is due to the lower bond energy of C=C than the C=O group. The additional...
2.8K
02:14Combustion Energy: A Measure of Stability in Alkanes and Cycloalkanes
6.4K
The low reactivity in alkanes can be attributed to the non-polar nature of C–C and C–H σ bonds. Alkanes, therefore, were initially termed as “paraffins,” derived from the Latin words: parum, meaning “too little,” and affinis, meaning “affinity.”
Alkanes undergo combustion in the presence of excess oxygen and high-temperature conditions to give carbon dioxide and water. A combustion reaction is the energy source in natural gas, liquified...
Alkanes undergo combustion in the presence of excess oxygen and high-temperature conditions to give carbon dioxide and water. A combustion reaction is the energy source in natural gas, liquified...
6.4K
01:28Stability of Conjugated Dienes
3.5K
Introduction
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.
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.
3.5K
01:59Relative Stabilities of Alkenes
14.1K
The relative stability of alkenes can be determined by comparing their heats of hydrogenation. The lower heat of hydrogenation indicates the more stable alkene. The three main factors determining the relative stability of alkenes are i) the number of substituents attached to the double-bond carbon atoms, ii) hyperconjugation, and iii) the stereochemistry of the double bond.
14.1K