Orthochems

Orthochems is a term found in some chemistry discussions to describe reagents or building blocks designed for use in orthogonal reaction systems. It is not a standard, universally defined category in peer‑reviewed literature, and its exact meaning can vary by author or context. In many sources, orthochems embodies a design philosophy rather than a formal taxonomy, emphasizing selective reactivity within complex mixtures.

The core idea behind orthochems is orthogonality: a reagent remains comparatively inert toward most functional groups or reaction conditions present, while offering a distinct trigger or pathway to react when desired. This enables selective transformations in multi-component or tightly packed settings. Design strategies often involve introducing reactive handles that are not engaged by common chemistries, employing protecting groups that can be removed under orthogonal conditions, or incorporating stimuli-responsive elements activated by light, pH, redox changes, or specific catalysts.

In practice, orthochems intersect with established concepts such as orthogonal protection schemes and bioorthogonal chemistry. They are discussed in the context of improving selectivity in complex synthetic sequences, enabling targeted labeling or modification in polymers, surfaces, or biological systems without disturbing other functionalities. Because the term lacks formal standardization, researchers typically define the scope of orthochems within their own work and rely on explicit definitions in their publications.

Related concepts include orthogonal chemistry, bioorthogonal reactions, and protecting-group strategies.