A chiral organocatalytic polymer-based monolithic reactor
作者:Valerio Chiroli、Maurizio Benaglia、Alessandra Puglisi、Riccardo Porta、Ravindra P. Jumde、Alessandro Mandoli
DOI:10.1039/c4gc00031e
日期:——
properly modified enantiomericallypure imidazolidinone inside a stainless steel column in the presence of dodecanol and toluene as porogens afforded the first example of a chiral organocatalyst immobilized onto a monolithic reactor. Organocatalyzed cycloadditionsbetween cyclopentadiene and cinnamic aldehyde were performed under continuous-flow conditions; by optimizing the experimental set up, excellent
New Strategies in Organic Catalysis: The First Enantioselective Organocatalytic Friedel−Crafts Alkylation
作者:Nick A. Paras、David W. C. MacMillan
DOI:10.1021/ja015717g
日期:2001.5.1
this catalytic strategy is also amenable to [3 + 2] cycloadditions between nitrones and α,β-unsaturatedaldehydes to provide isoxazolidines (eq 3), useful synthons for the construction of biologically important amino acids, β-lactams, amino carbohydrates, and alkaloids. To our knowledge, this is the first example of an organocatalytic 1,3-dipolar cycloaddition.3 Moreover, this study further documents
Chiral GAP catalysts of phosphonylated imidazolidinones and their applications in asymmetric Diels–Alder and Friedel–Crafts reactions
作者:Shuo Qiao、Junming Mo、Cody B. Wilcox、Bo Jiang、Guigen Li
DOI:10.1039/c6ob02801b
日期:——
The design and synthesis of recyclable imidazolidinone catalysts using GAP chemistry/technique was described. Their applications in asymmetric Diels–Alder and Friedel–Crafts reactions with α,β-unsaturatedaldehydes resulted in excellent yields and higher enantioselectivities than previous processes. As recyclable small molecular catalysts, phosphonylated imidazolidinones can be recovered and reused
描述了使用 GAP 化学/技术设计和合成可回收咪唑啉酮催化剂。它们在与 α,β-不饱和醛的不对称 Diels-Alder 和 Friedel-Crafts 反应中的应用比以前的工艺产生了优异的产率和更高的对映选择性。作为可回收的小分子催化剂,膦酰化咪唑啉酮可以回收并重复使用最多三次,而不会导致催化活性显着下降。
Enantioselective Catalysis over Chiral Imidazolidin-4-one Immobilized on Siliceous and Polymer-Coated Mesocellular Foams
作者:Yugen Zhang、Lan Zhao、Su Seong Lee、Jackie Y. Ying
DOI:10.1002/adsc.200600240
日期:2006.10
A highly efficient and enantioselective organocatalyst, imidazolidin-4-one, has been successfully immobilized on siliceous MCF and polymer-coated MCF. The resulting heterogenized catalyst demonstrated excellent catalyticperformance and recyclability for Friedel–Crafts alkylation and Diels–Aldercycloaddition. The performance of the supported catalysts in relation to the surface environment of siliceous
Intriguing imidazolidinones! Inspired by noncovalentinteractions in proteins, a series of electronically distinct MacMillancatalysts were designed. The effect of electronic modulation on ground state conformation, reactivity, and performance was studied in a catalytic setting with intriguing outcomes.