Interlocked Molecules in Enantioselective Catalysis

2021 ◽  
pp. 69-80
Author(s):  
Carel Kwamen ◽  
Jochen Niemeyer
Keyword(s):  
Enantioselective Catalysis ◽  
Interlocked Molecules

A Mechanically Planar Chiral Rotaxane Ligand for Enantioselective Catalysis

2019 ◽  
Author(s):  
Andrew Heard ◽  
Stephen Goldup
Keyword(s):  
Active Site ◽  
Molecular Machines ◽  
Enantioselective Catalysis ◽  
Interlocked Molecules ◽  
End Groups ◽  
Mechanical Bond

<p> <b>Rotaxanes are interlocked molecules in which a molecular ring is trapped on a dumbbell-shaped axle due to its inability to escape over the bulky end groups, resulting in a so-called mechanical bond. Interlocked molecules have mainly been studied as components of molecular machines, but the crowded, flexible environment created by threading one molecule through another, reminiscent of the active site of an enzyme, has also been explored in catalysis and sensing. However, so far the applications of one of the most intriguing properties of interlocked molecules, their ability to display stereogenic units that do not rely on the stereochemistry of their covalent subunits, termed "mechanical chirality", have yet to be properly explored and prototypical demonstration of the applications of mechanically chiral rotaxanes remain scarce. Here we describe a mechanically planar chiral rotaxane-based Au complex that mediates a cyclopropanation reaction with stereoselectivities that are comparable with conventional covalent catalyst reported for this reaction.</b></p>

A Mechanically Planar Chiral Rotaxane Ligand for Enantioselective Catalysis

2019 ◽  
Author(s):  
Andrew Heard ◽  
Stephen Goldup
Keyword(s):  
Active Site ◽  
Molecular Machines ◽  
Enantioselective Catalysis ◽  
Interlocked Molecules ◽  
End Groups ◽  
Mechanical Bond

<p> <b>Rotaxanes are interlocked molecules in which a molecular ring is trapped on a dumbbell-shaped axle due to its inability to escape over the bulky end groups, resulting in a so-called mechanical bond. Interlocked molecules have mainly been studied as components of molecular machines, but the crowded, flexible environment created by threading one molecule through another, reminiscent of the active site of an enzyme, has also been explored in catalysis and sensing. However, so far the applications of one of the most intriguing properties of interlocked molecules, their ability to display stereogenic units that do not rely on the stereochemistry of their covalent subunits, termed "mechanical chirality", have yet to be properly explored and prototypical demonstration of the applications of mechanically chiral rotaxanes remain scarce. Here we describe a mechanically planar chiral rotaxane-based Au complex that mediates a cyclopropanation reaction with stereoselectivities that are comparable with conventional covalent catalyst reported for this reaction.</b></p>

A Mechanically Planar Chiral Rotaxane Ligand for Enantioselective Catalysis

2019 ◽  
Author(s):  
Andrew Heard ◽  
Stephen Goldup
Keyword(s):  
Active Site ◽  
Molecular Machines ◽  
Enantioselective Catalysis ◽  
Interlocked Molecules ◽  
End Groups ◽  
Mechanical Bond

<p> <b>Rotaxanes are interlocked molecules in which a molecular ring is trapped on a dumbbell-shaped axle due to its inability to escape over the bulky end groups, resulting in a so-called mechanical bond. Interlocked molecules have mainly been studied as components of molecular machines, but the crowded, flexible environment created by threading one molecule through another, reminiscent of the active site of an enzyme, has also been explored in catalysis and sensing. However, so far the applications of one of the most intriguing properties of interlocked molecules, their ability to display stereogenic units that do not rely on the stereochemistry of their covalent subunits, termed "mechanical chirality", have yet to be properly explored and prototypical demonstration of the applications of mechanically chiral rotaxanes remain scarce. Here we describe a mechanically planar chiral rotaxane-based Au complex that mediates a cyclopropanation reaction with stereoselectivities that are comparable with conventional covalent catalyst reported for this reaction.</b></p>

Heterogeneous Enantioselective Catalysis with Chiral Encoded Mesoporous Pt−Ir Films Supported on Ni Foam

2021 ◽  
Author(s):  
Sunpet Assavapanumat ◽  
Sopon Butcha ◽  
Somlak Ittisanronnachai ◽  
Alexander Kuhn ◽  
Chularat Wattanakit
Keyword(s):  
Enantioselective Catalysis ◽  
Ni Foam

scholarly journals π-Stacking Stopper-Macrocycle Stabilized Dynamically Interlocked [2]Rotaxanes

Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4704
Author(s):  
Sing-Ming Chan ◽  
Fung-Kit Tang ◽  
Ching-Yau Lam ◽  
Chak-Shing Kwan ◽  
Sam C. K. Hau ◽  
...  
Keyword(s):  
Crystal Structures ◽  
Thermodynamic Stability ◽  
Combinatorial Library ◽  
Aromatic Rings ◽  
Interlocked Molecules ◽  
X Ray ◽  
Π Stacking ◽  
Dynamic Combinatorial Library

The synthesis of mechanically interlocked molecules is valuable due to their unique topologies. With π-stacking intercomponent interaction, e.g., phenanthroline and anthracene, novel [2]rotaxanes have been synthesized by dynamic imine clipping reaction. Their X-ray crystal structures indicate the π-stackings between the anthracene moiety (stopper) on the thread and the (hetero)aromatic rings at the macrocycle of the rotaxanes. Moreover, the length of glycol chains affects the extra π-stacking intercomponent interactions between the phenyl groups and the dimethoxy phenyl groups on the thread. Dynamic combinatorial library has shown at best 84% distribution of anthracene-threaded phenanthroline-based rotaxane, coinciding with the crystallography in that the additional π-stacking intercomponent interactions could increase the thermodynamic stability and selectivity of the rotaxanes.

Calcium catalyzed enantioselective intramolecular alkene hydroamination with chiral C2-symmetric bis-amide ligands

2021 ◽  
Vol 50 (9) ◽  
pp. 3178-3185 ◽  
Author(s):  
Philipp C. Stegner ◽  
Jonathan Eyselein ◽  
Gerd M. Ballmann ◽  
Jens Langer ◽  
Jochen Schmidt ◽  
...  
Keyword(s):  
Enantioselective Catalysis ◽  
Amide Ligands ◽  
Calcium Catalysts

Enantioselective catalysis with calcium catalysts is challenging due to facile loss of the chiral spectator ligand. Herein a series of bis-amide calcium catalysts with chiral binaphtalene bridges is introduced.

Origin of Stereoinduction by Chiral Aminophosphane Phosphinite Ligands in Enantioselective Catalysis: Asymmetric Hydroformylation

2006 ◽  
Vol 12 (5) ◽  
pp. 1457-1467 ◽  
Author(s):  
Jorge J. Carbó ◽  
Agustí Lledós ◽  
Dieter Vogt ◽  
Carles Bo
Keyword(s):  
Enantioselective Catalysis ◽  
Asymmetric Hydroformylation

Asymmetrische Katalysen, 25 [1]. C5H5Mn(CO)2-Komplexe von optisch aktiven Chelatphosphanen als einzähnige Liganden in der enantioselektiven Katalyse / Asymmetric Catalyses, 25 [1]. C5H5Mn(CO)2 Complexes of Optically Active Chelate Phosphanes as Monodentate Ligands in Enantioselective Catalysis

1985 ◽  
Vol 40 (10) ◽  
pp. 1243-1249 ◽  
Author(s):  
Henri Brunner ◽  
Alfons Knott
Keyword(s):  
Cinnamic Acid ◽  
Enantioselective Hydrogenation ◽  
Optically Active ◽  
Enantioselective Catalysis ◽  
Dinuclear Complexes ◽  
Bidentate Ligands ◽  
Monodentate Ligand ◽  
Mononuclear Complexes ◽  
Monodentate Ligands

The chelate phosphanes Diphos, Diop, and Norphos were reacted with C5H5Mn(CO)2THF and CH3C5H4Mn(CO)2THF to give mononuclear complexes, containing the phosphanes as unidentate or as bidentate ligands, and dinuclear complexes, containing bridging phosphane ligands. In C5H5Mn(CO)2Diop one of the two P(C6H5)2 groups of Diop is coordinated to the C5H5Mn(CO)2 fragment; the uncoordinated P(C6H5)2 group makes it a monodentate ligand. C5H5Mn(CO)2Diop together with [Rh(cod)Cl]2 was used as an in situ catalyst in the enantioselective hydrogenation of (Z)-a-[N -acetam ino]cinnamic acid (78.4% ee) and in the enantioselective hydrosilylation of acetophenone with diphenylsilane (6.7% ee).

Sign in / Sign up

Export Citation Format

Share Document