Improved Scalable Synthesis of the (S,S)-DACH-Ph Trost Ligand
An Improved Scalable Process for the Synthesis of (S,S)-DACH-Ph Trost Ligand: Yongda Zhang, Eugene Chong, Jada A. H. White, Suttipol Radomkit, Yibo Xu, Stephanie C. Kosnik, Jon C. Lorenz
The (S,S)-DACH-Ph Trost ligand is an exceptionally effective and versatile ligand for the Pd-catalyzed asymmetric allylic alkylation of a diverse range of substrates to afford the corresponding chiral products with high yields and excellent levels of enantioselectivity. However, its synthesis has not been extensively studied and highly variable yields of this ligand – ranging from 30–90% – have been reported in the literature, with a purification by silica gel column chromatography generally required. Recently, a group of researchers at Boehringer Ingelheim Pharmaceuticals, Inc. (Ridgefield, USA), led by Dr. Yongda Zhang, reported an improved and optimized synthesis of the title ligand.
Professor Zhang said: “The economic, operationally simple, and scalable chemical process for preparation of (S,S)-DACH-Ph Trost ligand will promote its application in the asymmetric catalysis on large scale in industry.”