The N-tetrachlorophthaloyl-(TCP-)amino protecting group has been evaluated for use in solid-phasepeptidesynthesis. The TCP group was unaffected by exposure to either piperidine or N,N-diisopropylethylamine (DIEA), which suggests compatibility with both Fmoc and Boc solid-phasesynthesis protocols. Quantitative TCP removal was achieved by treatment with hydrazine/DMF (3:17) at 35 °C for 30 min or with