A New Method for the Preparation of 2-Chlorotrityl Chloride Resin

Significance

Polystyrene-supported 2-chlorotrityl chloride (2-CTC) was prepared and used as solid support for the solid-phase peptide synthesis. The reaction of 2-chlorobenzophenone 1 with PCl₅ gave 1-chloro-2-[dichloro(phenyl)methyl]benzene 2 in 90% yield (eq. 1). The Friedel-Crafts reaction of compound 2 with 1% divinylbenzene-crosslinked polystyrene 3 in the presence of AlCl₃ gave the polymer-supported 2-chlorotrityl alcohol 4, and the chlorination of the resulting alcohol 4 with SOCl₂ gave 2-CTC resin 5 (eq. 2). Four peptide fragments (T-20 1-16, T-20 17-26, T-20 27-35, and ACP 65-74) were prepared by using the 2-CTC resin 5 with high purity.