title: Chiral calcium iodide for asymmetric Mannich-type reactions of malonates with imines providing β-aminocarbonyl compounds.
abstract: Out of the pybox: We have developed a novel chiral calcium iodide catalyst from CaI2 and a pybox that is stable under moisture and oxygen. This catalyst was applied to catalytic asymmetric Mannich-type reactions of malonates with both N-Boc-protected aromatic and aliphatic imines, and resulted in moderate to high yields with high enantioselectivities. To the best of our knowledge, this is the first example of highly enantioselective metal-catalyzed asymmetric Mannich-type reactions of malonates with N-Boc-protected aliphatic imines. The Mannich adduct was successfully converted into the α-hydroxy β-amino acid derivative. We have also shown the unique structure of the chiral Ca complexes with malonates.
authors.affiliation: Department of Chemistry, School of Science, The University of Tokyo, Tokyo, Japan.
authors.forename: Tetsu
authors.initials: T
authors.lastname: Tsubogo
authors.forename: Shota
authors.initials: S
authors.lastname: Shimizu
authors.forename: Shū
authors.initials: S
authors.lastname: Kobayashi
mesh_terms: D000596:Amino Acids / Q000138:chemical synthesis* / Q000737:chemistry; D002118:Calcium / Q000737:chemistry*; D002384:Catalysis; D007097:Imines / Q000737:chemistry*; D007454:Iodides / Q000737:chemistry*; D008314:Malonates / Q000737:chemistry*; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D000596:Amino Acids; D007097:Imines; D007454:Iodides; D008314:Malonates; D002118:Calcium