2921.45 - 1-Naphthylamine (α-Naphthylamine), 2-Naphthylamine (β-Naphthylamine), and their derivatives; salts thereof:

This HTS category, 2921.45, specifically encompasses 1-naphthylamine (α-naphthylamine), 2-naphthylamine (β-naphthylamine), and their various derivatives, as well as the salts formed from these compounds. These substances are aromatic monoamines characterized by the presence of a naphthyl group, which is a fused bicyclic aromatic ring system. This distinction is crucial for accurate classification, differentiating them from simpler aromatic amines like aniline or toluidine.

Unlike sibling categories such as 2921.41 (Aniline and its salts) or 2921.43 (Toluidines and their derivatives), category 2921.45 focuses exclusively on compounds derived from naphthylamine. While 2921.42 covers aniline derivatives, it does not extend to the more complex naphthylamine structures. Similarly, category 2921.44 deals with diphenylamine, a different diarylamine. The further subdivisions under 2921.45.20.00 and 2921.45.25.00 detail specific sulfonated naphthylamine derivatives and mixtures, highlighting the importance of the presence and position of functional groups like sulfonic acid for granular classification within this branch. The "Other" subcategory serves as a residual category for any remaining naphthylamine derivatives not explicitly listed.