A Chromatography-free Method for the Isolation of Products from Mechanochemical Reactions - Ball Milling Towards Green Synthesis: Applications, Projects, Challenges - page 194

Cl Leu Ala-Leu

1|Leu
2) Filter

1|)Ala
2) Filter

1|)Gly
2) Filter

Leu-Ala-Gly Leu-Ala-Gly-Val

1|)Ala
2) Filter

NaOH

Leu-Ala-Gly-Val

Scheme 8.2 Synthesis of tetrapeptide using a polystyrene cross-linked resin.

Reprinted (adapted) with permission from ref. 19. Copyright 1963 American Chemical Society.