142765-23-9Relevant articles and documents
Chiral Heterobimetallic Bismuth–Rhodium Paddlewheel Catalysts: A Conceptually New Approach to Asymmetric Cyclopropanation
Collins, Lee R.,Auris, Sebastian,Goddard, Richard,Fürstner, Alois
, p. 3557 - 3561 (2019)
Cyclopropanation reactions of styrene derivatives with donor–acceptor carbenes formed in situ are significantly more enantioselective when catalyzed by the heterobimetallic bismuth–rhodium complex 5 a endowed with N-phthalimido tert-leucine paddlewheel ligands rather than by its homobimetallic dirhodium analogue 1 a. This virtue is likely the result of two synergizing factors: the conical shape of 5 a translates into a narrower calyx-like chiral binding site about the catalytically active Rh center; the Bi atom, although fully solvent exposed, does not decompose aryl diazoacetates and is hence incapable of promoting a racemic background reaction. Moreover, ligand variation proved that successful catalyst design mandates that the anisotropy of the conical heterobimetallic core be matched by proper directionality of the ligand sphere.
Chiral amide compound and synthesis method thereof
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Paragraph 0020-0021, (2021/11/26)
The invention relates to a chiral amide compound and a synthesis method thereof, wherein the structural general formula of the chiral amide compound is. A chiral carboxylic acid is used as a basic raw material, a carboxyl group is converted into acid chloride and condensed with an aliphatic amine or an alkoxyamine group, the chiral amide is synthesized in a high yield, and the reaction operation is simple and efficient. The chiral amino acid is taken as a raw material, the amide compound is synthesized through a simple three-step method, the yield is high, the chirality of the obtained compound is determined by the chiral decision of the amino acid of the raw material, and the substrate selection range is wide. The obtained amide compound can be used as a ligand, has a plurality of sites and can be modified, so that the electric property of the ligand can be changed, and the steric hindrance of the ligand can be increased so as to adapt to different catalytic reactions.
Amino acid chiral ligand containing bidentate coordination group, chiral catalyst, and corresponding preparation methods and applications thereof
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Paragraph 0073, (2019/10/02)
The present invention relates to an amino acid chiral ligand containing a bidentate coordination group, a chiral catalyst, and corresponding preparation methods and applications thereof. The chiral ligand is prepared from a cheap and easily available amino acid, and the development of the chiral ligand can improve the diversity of the chiral ligand. The chiral Ir (III) catalyst is simply and efficiently prepared from the chiral ligand only through a one-step reaction. The chiral Ir (III) catalyst is characterized in that a bidentate guiding group is introduced to an amino acid framework to change the original coordination mode of the amino acid and Ir in order to enhance the chiral control ability of the amino acid to the Ir(III) catalyst. The chiral Ir(III) catalyst is designed and synthesized for the first time, and the selectivity reaches up to 99% ee when the catalyst is successfully applied to the high-efficiency asymmetric synthesis of chiral gamma-cyclolactam, so the catalyst has superior stereo control ability.
