Pd-catalyzed asymmetric allylic alkylation of glycine imino ester using a chiral phase-transfer catalyst
| Autor: | Tomotaka Okino, Masayoshi Nakoji, Yoshiji Takemoto, Takatoshi Kanayama |
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| Rok vydání: | 2002 |
| Předmět: |
Models
Molecular Alkylation Allyl compound Glycine Molecular Conformation Salt (chemistry) Medicinal chemistry Catalysis chemistry.chemical_compound Tsuji–Trost reaction Structure-Activity Relationship Organic chemistry chemistry.chemical_classification Ligand Organic Chemistry Chiral ligand Enantioselective synthesis Esters General Medicine Amino acid Allyl Compounds chemistry Phosphine Palladium |
| Zdroj: | The Journal of organic chemistry. 67(21) |
| ISSN: | 0022-3263 |
| Popis: | Pd-catalyzed asymmetric allylic alkylation of the glycine imino ester 1a has been developed using a chiral quaternary ammonium salt 3d without chiral phosphine ligands. The proper choice of the achiral Pd ligand, P(OPh)3, is important to achieve high enantioselectivity. By this method with the dual catalysts, numerous enantiomerically enriched alpha-allylic amino acids 4a-h could be prepared with comparable to higher enantioselectivity than that of the conventional asymmetric alkylation of 1a. In addition, the Pd-catalyzed reaction of 1a with 1-phenyl-2-propenyl acetate 2i afforded the branch product 6 with high enantio- and diastereoselectivity (95% de, 85% ee). |
| Databáze: | OpenAIRE |
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