scholarly journals Cupreines and cupreidines: an established class of bifunctional cinchona organocatalysts

2016 ◽  
Vol 12 ◽  
pp. 429-443 ◽  
Author(s):  
Laura A Bryant ◽  
Rossana Fanelli ◽  
Alexander J A Cobb
Keyword(s):  
Functional Groups ◽  
Bifunctional Catalyst ◽  
Cinchona Alkaloids ◽  
Asymmetric Organocatalysis

Cinchona alkaloids with a free 6'-OH functionality are being increasingly used within asymmetric organocatalysis. This fascinating class of bifunctional catalyst offers a genuine alternative to the more commonly used thiourea systems and because of the different spacing between the functional groups, can control enantioselectivity where other organocatalysts have failed. In the main, this review covers the highlights from the last five years and attempts to show the diversity of reactions that these systems can control. It is hoped that chemists developing asymmetric methodologies will see the value in adding these easily accessible, but underused organocatalysts to their screens.

ChemInform Abstract: Synergic Asymmetric Organocatalysis (SAOc) of Cinchona Alkaloids and Secondary Amines in the Synthesis of Bicyclo[2.2.2]octan-2-ones.

ChemInform ◽  
2009 ◽  
Vol 40 (25) ◽  
Author(s):  
Marco Bella ◽  
Daniele M. Scarpino Schietroma ◽  
Pier Paolo Cusella ◽  
Tecla Gasperi ◽  
Valerio Visca
Keyword(s):  
Cinchona Alkaloids ◽  
Secondary Amines ◽  
Asymmetric Organocatalysis

scholarly journals Horizons in Asymmetric Organocatalysis: En Route to the Sustainability and New Applications

Catalysts ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 101
Author(s):  
Sandra Ardevines ◽  
Eugenia Marqués-López ◽  
Raquel P. Herrera
Keyword(s):  
Animal Feed ◽  
Cinchona Alkaloids ◽  
Point Of View ◽  
Added Value ◽  
Small Organic Molecules ◽  
The Road ◽  
Chiral Compounds ◽  
History Of ◽  
Asymmetric Organocatalysis ◽  
New Applications

Nowadays, the development of new enantioselective processes is highly relevant in chemistry due to the relevance of chiral compounds in biomedicine (mainly drugs) and in other fields, such as agrochemistry, animal feed, and flavorings. Among them, organocatalytic methods have become an efficient and sustainable alternative since List and MacMillan pioneering contributions were published in 2000. These works established the term asymmetric organocatalysis to label this area of research, which has grown exponentially over the last two decades. Since then, the scientific community has attended to the discovery of a plethora of organic reactions and transformations carried out with excellent results in terms of both reactivity and enantioselectivity. Looking back to earlier times, we can find in the literature a few examples where small organic molecules and some natural products could act as effective catalysts. However, with the birth of this type of catalysis, new chemical architectures based on amines, thioureas, squaramides, cinchona alkaloids, quaternary ammonium salts, carbenes, guanidines and phosphoric acids, among many others, have been developed. These organocatalysts have provided a broad range of activation modes that allow privileged interactions between catalysts and substrates for the preparation of compounds with high added value in an enantioselective way. Here, we briefly cover the history of this chemistry, from our point of view, including our beginnings, how the field has evolved during these years of research, and the road ahead.

scholarly journals Cinchona Alkaloids in Asymmetric Organocatalysis

Synthesis ◽  
2012 ◽  
Vol 44 (13) ◽  
pp. 2114-2114 ◽  
Author(s):  
Tommaso Marcelli ◽  
Henk Hiemstra
Keyword(s):  
Cinchona Alkaloids ◽  
Asymmetric Organocatalysis

ChemInform Abstract: Cinchona Alkaloids in Asymmetric Organocatalysis

ChemInform ◽  
2010 ◽  
Vol 41 (27) ◽  
pp. no-no
Author(s):  
Tommasco Marcelli ◽  
Henk Hiemstra
Keyword(s):  
Cinchona Alkaloids ◽  
Asymmetric Organocatalysis

Cinchona Alkaloids in Asymmetric Organocatalysis

Synthesis ◽  
2010 ◽  
Vol 2010 (08) ◽  
pp. 1229-1279 ◽  
Author(s):  
Tommaso Marcelli ◽  
Henk Hiemstra
Keyword(s):  
Cinchona Alkaloids ◽  
Asymmetric Organocatalysis

Improving integration between functional groups: A case in organization change and implications for theory and practice

1971 ◽  
Author(s):  
Warren G. Bennis ◽  
Michael Beer ◽  
Gerald R. Pieters ◽  
Alan T. Hundert ◽  
Samuel H. Marcus ◽  
...  
Keyword(s):  
Functional Groups ◽  
Organization Change ◽  
Theory And Practice

HYDROXYAPATITE, ALGINATE, AND CHITOSAN FOR BONE SCAFFOLDS: SPECTROSCOPY STUDY

2016 ◽  
Vol 19 (2) ◽  
pp. 93-100
Author(s):  
Lalita El Milla
Keyword(s):  
Tissue Engineering ◽  
Bone Tissue Engineering ◽  
Bone Tissue ◽  
Functional Groups ◽  
Bone Growth ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Tissue Engineering Scaffolds ◽  
Hydroxyapatite Powder ◽  
Materials Used

Scaffolds is three dimensional structure that serves as a framework for bone growth. Natural materials are often used in synthesis of bone tissue engineering scaffolds with respect to compliance with the content of the human body. Among the materials used to make scafffold was hydroxyapatite, alginate and chitosan. Hydroxyapatite powder obtained by mixing phosphoric acid and calcium hydroxide, alginate powders extracted from brown algae and chitosan powder acetylated from crab. The purpose of this study was to examine the functional groups of hydroxyapatite, alginate and chitosan. The method used in this study was laboratory experimental using Fourier Transform Infrared (FTIR) spectroscopy for hydroxyapatite, alginate and chitosan powders. The results indicated the presence of functional groups PO43-, O-H and CO32- in hydroxyapatite. In alginate there were O-H, C=O, COOH and C-O-C functional groups, whereas in chitosan there were O-H, N-H, C=O, C-N, and C-O-C. It was concluded that the third material containing functional groups as found in humans that correspond to the scaffolds material in bone tissue engineering.

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