Synthesis of Cinchona Alkaloid-Derived Chiral Polymers by Mizoroki–Heck Polymerization and Their Application to Asymmetric Catalysis

2014 ◽  
Vol 47 (6) ◽  
pp. 1922-1928 ◽  
Author(s):  
Md. Masud Parvez ◽  
Naoki Haraguchi ◽  
Shinichi Itsuno
Keyword(s):  
Asymmetric Catalysis ◽  
Cinchona Alkaloid ◽  
Chiral Polymers

Synthesis of cinchona alkaloid sulfonamide polymers as sustainable catalysts for the enantioselective desymmetrization of cyclic anhydrides

RSC Advances ◽  
2016 ◽  
Vol 6 (76) ◽  
pp. 72300-72305 ◽  
Author(s):  
Shohei Takata ◽  
Yuta Endo ◽  
Mohammad Shahid Ullah ◽  
Shinichi Itsuno
Keyword(s):  
Cinchona Alkaloid ◽  
High Yield ◽  
Chiral Polymers ◽  
Cyclic Anhydrides

Mizoroki–Heck polymerization of cinchona sulfonamide gave chiral polymers, which are active catalysts for enantioselective desymmetrization of cyclic anhydrides to give chiral hemiesters in high yield with high enantioselectivities.

scholarly journals ADMET Polymerization of Dimeric Cinchona Squaramides for the Preparation of a Highly Enantioselective Polymeric Organocatalyst

Catalysts ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 591
Author(s):  
Mohammad Shahid Ullah ◽  
Sadia Afrin Chhanda ◽  
Shinichi Itsuno
Keyword(s):  
Second Generation ◽  
Michael Reaction ◽  
Cinchona Alkaloids ◽  
Cinchona Alkaloid ◽  
Acyclic Diene Metathesis ◽  
Chiral Polymers ◽  
Admet Polymerization ◽  
Reaction Condition ◽  
High Yields ◽  
Asymmetric Michael Reaction

Under the acyclic diene metathesis (ADMET) reaction condition, the C3-vinyl groups of cinchona alkaloids readily react with each other to form a C-C bond. A novel type of cinchona alkaloid polymers was synthesized from dimeric cinchona squaramides using the Hoveyda-Grubbs’ second-generation catalysts (HG2) by means of ADMET reaction. The chiral polymers, containing cinchona squaramide moieties in their main chains, were subsequently employed as catalysts for the enantioselective Michael reaction to give the corresponding chiral adducts in high yields with excellent enantioselectivity and diastereoselectivity. Both enantiomers from the asymmetric Michael reaction were distinctively prepared while using the polymeric catalysts, possessing pseudoenantiomeric structures. The catalysts were readily recovered from the reaction mixture and recycled several times due to the insolubility of the cinchona-based squaramide polymers.

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