Chiral Calcium Iodide for Asymmetric Mannich‐type Reactions of Malonates with Imines Providing β‐Aminocarbonyl Compounds. Issue 5 (11th March 2013)

• Record Type: Journal Article
• Authors: Tsubogo, Tetsu; Shimizu, Shota; Kobayashi, Shū
• Is Part Of: Chemistry, an Asian journal. Volume 8:Issue 5(2013:May)
• Page Start: 872
• Page End: 876
• Publication Date: 2013-03-11
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1002/asia.201300102
• Languages: English
• ISSNs: 1861-4728

Abstract

<abstract abstract-type="graphical" xml:lang="en"> <title> <x xml:space="preserve">Abstract</x> </title> <p> <bold>Out of the pybox</bold>: 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 <italic>N</italic>‐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 <italic>N</italic>‐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.<boxed-text content-type="graphic" position="anchor" orientation="portrait"><graphic position="anchor" mimetype="image" xlink:href="ark:/27927/pgg4t76zh53" orientation="portrait" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /></boxed-text></p> </abstract>