Enantioselective synthesis of furyl-substituted pyrrolidines

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2019
Araz, Mihrimah
Asymmetric 1,3-Dipolar Cycloaddition (DC) reactions of azomethine ylides are important for the synthesis of pyrrolidines. These reactions may give enantiomerically pure compounds in the presence of a chiral catalyst in a single step. Therefore, many groups have studied this reaction to synthesize aryl-substituted pyrrolidines in enantiomerically rich form. Although the aryl-substituted pyrrolidine synthesis is very common, the studies involving the heteroaryl-substituted pyrrolidines are quite rare. In general, groups studying these reactions mainly focus on the aryl-substituted pyrrolidines and include one or two examples involving the heteroaryl-substituted pyrrolidines. Therefore, it is important to synthesize different derivatives of heteroaryl-substituted pyrrolidines and develop a chiral catalyst that produces these compounds in high yields and enantioselectivities. Our group is also involved in this field and developed two different types of chiral ligands, one is known as ferrocenyl aziridinyl methanol (FAM) and the other one is the phosphorous derivative of these ligands. Using both ligands, our group reported the enantioselective synthesis of arylsubstituted pyrrolidines in good yields and enantioselectivities. In this thesis, we have applied our FAM ligands (four diastereomers) and a new derivative, namely 1naphthyl ferrocenyl aziridinyl methanol (1-NFAM, also four diastereomers), in the enantioselective synthesis of furyl-substituted pyrrolidines by using 1,3-DC reaction of azomethine ylides. Our studies showed that FAM ligands can catalyze the 1,3-DC reaction of azomethine ylides to form furyl-substituted pyrrolidines in up to 87% yield and 72% enantioselectivity.

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Citation Formats
M. Araz, “Enantioselective synthesis of furyl-substituted pyrrolidines,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Chemistry., Middle East Technical University, 2019.