Boc-Phe(3-CF3)-OH is primarily used in peptide synthesis as a building block for introducing trifluoromethylated phenylalanine residues into peptide chains. The trifluoromethyl group enhances the hydrophobicity and metabolic stability of the peptides, making it valuable in drug discovery and development. It is particularly useful in creating peptide-based therapeutics, enzyme inhibitors, and probes for studying protein-protein interactions. The Boc protecting group ensures selective deprotection during solid-phase peptide synthesis, allowing for precise control over the assembly of complex peptide structures. Its application is also explored in materials science for designing peptides with unique properties for nanotechnology and biomaterials.