Straightforward synthesis of [(2S,4R)-1-cyclohexyl-4-methylpiperidin-2-yl]methanol and [(2S,4R)-1-cyclohexyl-4-methylpiperidin-2-yl](diphenyl)methanol: novel chiral ligands for the catalytic addition of diethylzinc to benzaldehyde to give rise to an extensive turn in the sense of asymmetric induction

2010 ◽  
Vol 21 (19) ◽  
pp. 2334-2345 ◽  
Author(s):  
Carlos Alvarez-Ibarra ◽  
Juan F. Collados Luján ◽  
María L. Quiroga-Feijóo
Keyword(s):  
Asymmetric Induction ◽  
Chiral Ligands ◽  
Catalytic Addition

scholarly journals Exploiting the Chiral Ligands of Bis(imidazolinyl)- and Bis(oxazolinyl)thiophenes—Synthesis and Application in Cu-Catalyzed Friedel–Crafts Asymmetric Alkylation

Molecules ◽  
2021 ◽  
Vol 26 (23) ◽  
pp. 7408
Author(s):  
Mohammad Shahidul Islam ◽  
Abdullah Saleh Alammari ◽  
Assem Barakat ◽  
Saeed Alshahrani ◽  
Matti Haukka ◽  
...  
Keyword(s):  
Dicarboxylic Acid ◽  
Optical Purity ◽  
Chemical Yield ◽  
Amino Alcohols ◽  
Asymmetric Induction ◽  
Chiral Ligands ◽  
Tridentate Ligand ◽  
Asymmetric Alkylation

Five new C2-symmetric chiral ligands of 2,5-bis(imidazolinyl)thiophene (L1–L3) and 2,5-bis(oxazolinyl)thiophene (L4 and L5) were synthesized from thiophene-2,5-dicarboxylic acid (1) with enantiopure amino alcohols (4a–c) in excellent optical purity and chemical yield. The utility of these new chiral ligands for Friedel–Crafts asymmetric alkylation was explored. Subsequently, the optimized tridentate ligand L5 and Cu(OTf)2 catalyst (15 mol%) in toluene for 48 h promoted Friedel–Crafts asymmetric alkylation in moderate to good yields (up to 76%) and with good enantioselectivity (up to 81% ee). The bis(oxazolinyl)thiophene ligands were more potent than bis(imidazolinyl)thiophene analogues for the asymmetric induction of the Friedel–Crafts asymmetric alkylation.

scholarly journals Asymmetric catalytic addition of diorganozinc reagents to imines: Scope and application

2005 ◽  
Vol 77 (7) ◽  
pp. 1259-1267 ◽  
Author(s):  
André B. Charette ◽  
Alessandro A. Boezio ◽  
Alexandre Côté ◽  
Elaine Moreau ◽  
Julien Pytkowicz ◽  
...  
Keyword(s):  
Metal Complex ◽  
Asymmetric Induction ◽  
Asymmetric Catalytic ◽  
Catalytic Addition ◽  
High Degree ◽  
Very High

The copper-catalyzed diorganozinc addition to N-diphenylphosphinoylimines was shown to proceed with a very high degree of enantiocontrol if the reaction was run in the presence of Me-DuPHOS monoxide ligand (BozPHOS). The scope of the reaction is described as well as our efforts to identify the nature of the enantioactive metal complex responsible for the high asymmetric induction.

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