(R)-1-[3,5-Bis(trifluoromethyl)phenyl]ethanamine is a chiral amine derivative characterized by a 3,5-bis(trifluoromethyl)phenyl group attached to a chiral ethylamine core. The presence of the strongly electron-withdrawing trifluoromethyl groups and the chiral center are key structural features that define its utility. This compound is primarily employed as a high-value chiral building block or intermediate in pharmaceutical research and development. Its most notable application is in the synthesis of Aprepitant (Emend®), a neurokinin-1 (NK1) receptor antagonist used for the prevention of chemotherapy-induced nausea and vomiting (CINV). The chiral amine moiety serves as a critical pharmacophore in the final drug molecule. The compound is also used in the synthesis of other bioactive molecules and as a chiral ligand or resolving agent in asymmetric synthesis due to its bulky, electron-deficient aromatic system. As a specialty chemical, it is typically handled under controlled conditions in research and pilot-scale synthesis. Its synthesis and use require expertise in handling air- and moisture-sensitive reagents and performing chiral separations or asymmetric transformations.