Diastereo- and Enantioselective Three-Component Coupling Approach to Highly Substituted Pyrrolidines

FAM-Ag-catalyzed asymmetric synthesis of heteroaryl-substituted pyrrolidines

New derivatives of FAM (ferrocenyl aziridinyl methanol) ligands NFAM1-4 (naphthyl ferrocenyl aziridinyl methanol) and CFAM1-4 (cyclohexyl ferrocenyl aziridinyl methanol) were synthesized to form a small ligand library and used as chiral catalysts with AgOAc for the asymmetric synthesis of heteroaryl-substituted pyrrolidines by the 1,3-dipolar cycloaddition (1,3-DC) reaction of azomethine ylides. 2-Thienyl, 2-furyl, 2-, 3-, and 4-pyridyl aldimines were prepared and used with N-methylmaleimide, dimethyl maleate, tert-butyl acrylate, methyl acrylate, and acrylonitrile to form the corresponding heteroaryl-substituted pyrrolidines. 1,3-DC reactions yielded the expected cycloadducts in up to 89% yield and up to 76% ee that could be increased up to 95% ee upon crystallization. New chiral ligands NFAM1-4 and CFAM1-4 were fully characterized, and their absolute stereochemistry was determined by single-crystal X-ray analysis.

Design and Synthesis of Pyrrolidine-based Fragments That Sample Three-dimensional Molecular Space

Fragment-based drug discovery (FBDD) is a well-established technology for lead compound generation in drug discovery. As this technology has evolved, the design of fragments for screening has also evolved to engender not just an understanding of the role of modulating the physicochemical properties of fragments (Rule of Three, Ro3) but also the importance and implications of incorporating shape and, in particular, 3D characteristics into fragments. Herein, we describe the design and synthesis of pyrrolidine-based fragments with good fragment-like (Ro3) physicochemical properties that effectively sample three-dimensional molecular space.

Synthesis of pyrrolidine-3-carboxylic acid derivatives via asymmetric Michael addition reactions of carboxylate-substituted enones

An enantioselective Michael addition reaction system was developed. Using the reaction system, 5-methylpyrrolidine-3-carboxylic acid was synthesized in two steps.

Ligand-Controlled Diastereoselective 1,3-Dipolar Cycloadditions of Azomethine Ylides with Methacrylonitrile

Copper-catalyzed reactions of glycine ester arylimines and methacrylonitrile provide selective access to either the endo or exo pyrrolidine cycloadducts. DFT calculations have elucidated the origins of ligand-controlled diastereoselectivity.