使用正面和未标记的机器学习预测醇氧化同合中的基质活性
Takafumi Nishii1, Kaname Ichizawa1, Haruka Nagano1
1Department of Chemistry and Life Science, Yokohama National University, Hodogaya-Ku, Yokohama 240-8501, Japan.
ACS omega
|November 3, 2025
概括
一个新的机器学习模型预测了氧化同对基质的反应性. 这种积极和未标记的 (PU) 学习方法在不需要负数据的情况下实现了高准确性,从而实现了具有成本效益的分子合成.
科学领域:
- 有机化学 有机化学
- 机器学习 机器学习
- 计算化学的计算化学
背景情况:
- 预测基质反应性对于高效的有机合成至关重要.
- 的氧化同是一种具有广泛应用的关键反应.
- 传统的机器学习模型通常需要广泛的标记数据,包括负面示例.
研究的目的:
- 开发和验证一个积极和未标记的 (PU) 学习模型,用于预测氧化同合中的基质反应性.
- 用不同的描述器集和实验数据来评估模型的预测性能.
- 为了证明PU学习在化学合成预测中的传统方法上的优势.
主要方法:
- 训练PU学习模型来预测基质反应性.
- 使用两个描述符集用于模型验证:28维描述符和扩展连接指纹.
- 使用实验数据进行参数调整,以优化模型性能.
- 使用未标记的数据评估预测准确性,并与经过积极和消极数据训练的模型进行比较.
主要成果:
- 优化的PU学习模型在各种反应条件下,在现有实验数据上实现了出色的预测准确性.
- 使用30种未标记数据的预测与实验结果对83.3-86.7%的基质有很好的相关性.
- 与与正和负反应率数据一起训练的模型相比,PU学习模型表现出更高的准确性.
结论:
- PU学习是一种有效的策略,用于预测氧化同合中的基质反应性.
- 开发的模型提供了高的预测能力,而不需要负的实验数据.
- 这种方法通过利用易于获得的文献数据,促进了具有成本效益的分子合成.
更多相关视频
相关概念视频
02:24Predicting Reaction Outcomes
9.9K
Kinetics describes the rate and path by which a reaction occurs. In contrast, thermodynamics deals with state functions and describes the properties, behavior, and components of a system. It is not concerned with the path taken by the process and cannot address the rate at which a reaction occurs. Although it does provide information about what can happen during a reaction process, it does not describe the detailed steps of what appears on an atomic or a molecular level. On the other hand,...
9.9K
02:52Predicting Products: Substitution vs. Elimination
13.8K
When a nucleophile and an alkyl halide react, nucleophilic substitution and β-elimination reactions compete to generate products.
The following factors can influence the mechanisms competing against each other:
The following factors can influence the mechanisms competing against each other:
13.8K
01:17Oxidation of Phenols to Quinones
4.5K
In the presence of oxidizing agents, phenols are oxidized to quinones. Quinones can be easily reduced back to phenols using mild reducing agents. The electron-donating hydroxyl group enhances the reactivity of the aromatic ring, enabling oxidation of the ring even in the absence of an α hydrogen.
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...
4.5K
02:27Predicting Products: SN1 vs. SN2
15.9K
Nucleophilic substitution reactions of alkyl halides can proceed via an SN1 or an SN2 mechanism. While in SN2 reactions, the nucleophile attacks the substrate simultaneously as the leaving group departs, in SN1 reactions, the substrate first dissociates to give the carbocation intermediate. Various factors such as the structure of the substrate, the strength of the nucleophile, and the nature of the solvent promote one mechanism over the other.
With increased substitution on the alkyl halide,...
With increased substitution on the alkyl halide,...
15.9K
02:34Nucleophilic Substitution Reactions
19.0K
Historical perspective
In 1896, the German chemist Paul Walden discovered that he could interconvert pure enantiomeric (+) and (-) malic acids through a series of reactions. This conversion suggested the involvement of optical inversion during the substitution reaction. Further, in 1930, Sir Christopher Ingold described for the first time two different forms of nucleophilic substitution reactions, which are known as SN1 (nucleophilic substitution unimolecular) and SN2 (nucleophilic substitution...
In 1896, the German chemist Paul Walden discovered that he could interconvert pure enantiomeric (+) and (-) malic acids through a series of reactions. This conversion suggested the involvement of optical inversion during the substitution reaction. Further, in 1930, Sir Christopher Ingold described for the first time two different forms of nucleophilic substitution reactions, which are known as SN1 (nucleophilic substitution unimolecular) and SN2 (nucleophilic substitution...
19.0K
01:01Classification of Titrimetric Analysis Based on Reaction Types
1.5K
Titrimetric analysis in solution chemistry involves measuring the volume of solutions and is often called volumetric analysis. The standard solution of known concentration in the burette is called the titrant, whereas the solution of unknown concentration in the flask is called the analyte, or titrand. Titrimetric analyses can be classified into four types based on the reactions between the titrant and analyte.
Titrations between an acid and a base lead to neutralization reactions that form...
Titrations between an acid and a base lead to neutralization reactions that form...
1.5K