2-Chlorotrityl chloride resin (200-400 mesh, 1.5-1.9 mmol/g)

A very acid sensitive resin suitable for the synthesis of protected peptide fragments by the Fmoc-strategy. ClTrt resin is in particular suitable for the preparation of C-terminal prolyl and cysteinyl peptides (please see 2-Chlorotrityl Chloride Resin-Linked Amino Acids). Release from this resin is achieved by using 1-50 % TFA in CH₂Cl₂ containing 8 % triisopropylsilane, AcOH/CF₃CH₂OH/CH₂Cl₂, 0.5 % TFA or hexafluoroisopropanol/CH₂Cl₂. ClTrt resin has been used in cyclization reactions under Heck reaction conditions, the solid phase synthesis of β-peptides via the Arndt-Eistert homologation of Fmoc-protected amino acid diazoketones and in Mannich reactions of alkynes, secondary amines and aldehydes in the presence of a copper (I) salt affording the corresponding aminomethylalkynyl adducts. 2-Chlorotrityl resin is highly suitable for the synthesis of peptide alcohols, e.g., peptaibols, and peptide ω-aminoalkylamides.