imidazolidinone salts incorporated into the polymer main chain. Main‐chain ionic polyesters functionalized with chiral imidazolidinone salts in the polymer main chain were synthesized by the neutralization polymerization of a chiral imidazolidinone dimer with selected aromatic disulfonic acids. These polyesters were used as heterogeneous organocatalysts in the asymmetric Diels–Alder reaction of trans‐cinnamaldehyde
Synthesis of Main-Chain Ionic Polymers of Chiral Imidazolidinone Organocatalysts and Their Application to Asymmetric Diels-Alder Reactions
作者:Naoki Haraguchi、Nagisa Takenaka、Aisyah Najwa、Yuta Takahara、Mah Kar Mun、Shinichi Itsuno
DOI:10.1002/adsc.201701016
日期:2018.1.4
Main‐chain ionic polymers incorporating chiral imidazolidinone moieties in the polymermainchain were successfully synthesized by the polyaddition reaction of a chiral imidazolidinone dimer with a disulfonic acid. The organocatalytic activities of these polymers were investigated in the asymmetric Diels–Alder reaction between trans‐cinnamaldehyde and 1,3‐cyclopentadiene. The catalytic performance
A recyclable fluorous organocatalyst for Diels–Alder reactions
作者:Qianli Chu、Wei Zhang、Dennis P. Curran
DOI:10.1016/j.tetlet.2006.10.101
日期:2006.12
Chiral fluorous imidazolidinone catalyst 2 provides consistently high enantioselectivities in Diels Alder reactions of dienes and alpha,beta-unsaturated aldehydes. The catalyst can be readily separated from the reaction products by fluorous solid-phase extraction, and recovered in excellent purity for direct reuse. (c) 2006 Elsevier Ltd. All rights reserved.
Poly(ethylene glycol)-Supported Chiral Imidazolidin-4-one: An Efficient Organic Catalyst for the Enantioselective Diels–Alder Cycloaddition
A tyrosine-derived imidazolidin-4-one was immobilized on a modified poly(ethylene glycol) and converted in situ into a soluble polymer-supported catalyst for the enantioselective Diels-Alder cycloaddition of acrolein to 1,3-cyclohexadiene (up to 92% ee) and 2,3-dimethyl-1,3-butadiene (73% ee). Catalyst recycling (up to four cycles) was accompanied by some loss of the chemical efficiency and marginal erosion of the enantioselectivity.