reactiontype

Reactiontype is a label used in chemistry informatics to categorize a chemical reaction by its core transformation or mechanism. It functions as a metadata field in reaction databases, cheminformatics tools, and predictive models to group reactions that share a common pattern or outcome.

The primary purpose of reactiontype is to enable efficient organization, retrieval, and analysis of reaction data. It supports tasks such as reaction prediction, library design, and data-driven modeling by providing a coarse or fine-grained view of how reactions proceed. In practice, reactiontype helps researchers compare similar transformations, annotate experimental results, and assess the distribution of reaction classes within a dataset.

Classification schemes for reactiontype vary. Many systems use broad categories such as substitution, addition, elimination, condensation, rearrangement, redox, cyclization, and polymerization. Some datasets employ more detailed subtypes (for example, SN1 or SN2 under substitution, E1 or E2 under elimination), while others collapse reactions into higher-level classes. The specific taxonomy often depends on the dataset, the modeling task, and the level of mechanistic detail required.

Determining reactiontype can be manual, by expert curation, or automatic, by applying pattern-minding rules or machine learning to reactant patterns, reagents, and observed transformations. Because different databases and models adopt different taxonomies, the term reactiontype is somewhat context-dependent and may be mapped to multiple labeling schemes across sources. See also reaction mechanism, named reaction, and cheminformatics.