title: Polymer-supported glyoxylate and alpha-imino acetates. Versatile reagents for the synthesis of alpha-hydroxycarboxylic acid and alpha-amino acid libraries.
abstract: Polymer-supported glyoxylate.monohydrate (3) and alpha-imino acetates (7) have been readily prepared from chloromethylated resin via two or three steps. The ene reactions of 3 with alkenes were successfully performed in the presence of Yb(OTf)3 (50 mol %) to afford, after cleavage from the polymer support, the corresponding alpha-hydroxycarboxylic acid esters in good yields. The reactions of 7 with silyl enolates, Danishefsky's diene, and alkenes also proceeded smoothly in the presence of Sc(OTf)3 (20 mol %) to give the corresponding alpha-amino acid, pyridone, and tetrahydroquinoline derivatives, respectively, in good yields.
authors: Graduate School of Pharmaceutical Sciences, The University of Tokyo, CREST, Japan Science and Technology Corporation (JST), Hongo, Bunkyou-ku, Tokyo 113-0033, Japan.
authors: S
authors: S
authors: Kobayashi
authors: R
authors: R
authors: Akiyama
authors: H
authors: H
authors: Kitagawa
mesh_terms: D000085:Acetates / Q000737:chemistry*; D000596:Amino Acids / Q000138:chemical synthesis*; D020650:Combinatorial Chemistry Techniques; D006038:Glyoxylates / Q000737:chemistry*; D006880:Hydroxy Acids / Q000138:chemical synthesis*; D007097:Imines / Q000138:chemical synthesis*; D007202:Indicators and Reagents; D011108:Polymers
chemical_list: D000085:Acetates; D000596:Amino Acids; D006038:Glyoxylates; D006880:Hydroxy Acids; D007097:Imines; D007202:Indicators and Reagents; D011108:Polymers