N,N,N',N'-Tetramethylchloroformamidinium hexafluorophosphate
CAS 94790-35-9
An amide bond is common. Making the right one between two crowded fragments can be anything but common.
TCFH shows why peptide coupling is more than "acid + amine." A carboxylic acid is often too reluctant to react directly, especially when both partners are sterically crowded. TCFH is a strong activating reagent; with N-methylimidazole it can generate highly reactive N-acyl imidazolium species that drive difficult amide formations. Its value is greatest where ordinary coupling methods struggle - but strong activation must still be balanced against epimerization and side reactions.
Published:
2026-09-03
