scholarly journals Thiourea-Catalyzed Asymmetric Michael Addition of Activated Methylene Compounds to α,β-Unsaturated Imides: Dual Activation of Imide by Intra- and Intermolecular Hydrogen Bonding.

ChemInform ◽  
2006 ◽  
Vol 37 (48) ◽  
Author(s):  
Tsubasa Inokuma ◽  
Yasutaka Hoashi ◽  
Yoshiji Takemoto
Keyword(s):  
Hydrogen Bonding ◽  
Michael Addition ◽  
Intermolecular Hydrogen Bonding ◽  
Asymmetric Michael Addition ◽  
Dual Activation

ChemInform Abstract: Fast, Solvent-Free and Hydrogen-Bonding-Mediated Asymmetric Michael Addition in a Ball Mill.

ChemInform ◽  
2012 ◽  
Vol 43 (34) ◽  
pp. no-no
Author(s):  
Yi-Feng Wang ◽  
Ru-Xiang Chen ◽  
Ke Wang ◽  
Bin-Bin Zhang ◽  
Zhao-Bo Li ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Michael Addition ◽  
Ball Mill ◽  
Solvent Free ◽  
Asymmetric Michael Addition

Novel ferrocene-based bifunctional amine–thioureas for asymmetric Michael addition of acetylacetone to nitroolefins

2015 ◽  
Vol 13 (17) ◽  
pp. 5054-5060 ◽  
Author(s):  
Xiaochen Ren ◽  
Chunyan He ◽  
Yingle Feng ◽  
Yonghai Chai ◽  
Wei Yao ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Efficient Method ◽  
Michael Addition ◽  
High Yield ◽  
Bifunctional Catalysts ◽  
Michael Adducts ◽  
Asymmetric Michael Addition ◽  
Multiple Hydrogen Bonding

An efficient method was developed to synthesize the ferrocene-based bifunctional amine–thioureas bearing multiple hydrogen-bonding donors. Asymmetric Michael addition of acetylacetone to nitroolefins catalyzed by these novel bifunctional catalysts affords the Michael adducts in high yield and moderate to excellent enantioselectivities.

Fast, solvent-free and hydrogen-bonding-mediated asymmetric Michael addition in a ball mill

2012 ◽  
Vol 14 (4) ◽  
pp. 893 ◽  
Author(s):  
Yi-Feng Wang ◽  
Ru-Xiang Chen ◽  
Ke Wang ◽  
Bin-Bin Zhang ◽  
Zhao-Bo Li ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Michael Addition ◽  
Ball Mill ◽  
Solvent Free ◽  
Asymmetric Michael Addition

Pyrrolidine-ureas as bifunctional organocatalysts for asymmetric Michael addition of ketone to nitroalkenes: unexpected hydrogen bonding effect

Tetrahedron ◽  
2010 ◽  
Vol 66 (51) ◽  
pp. 9703-9707 ◽  
Author(s):  
Xiao-Yu Cao ◽  
Jun-Cheng Zheng ◽  
Yu-Xue Li ◽  
Zhen-Cao Shu ◽  
Xiu-Li Sun ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Michael Addition ◽  
Asymmetric Michael Addition ◽  
Bonding Effect ◽  
Hydrogen Bonding Effect

scholarly journals New hydrogen-bonding organocatalysts: Chiral cyclophosphazanes and phosphorus amides as catalysts for asymmetric Michael additions

2014 ◽  
Vol 10 ◽  
pp. 224-236 ◽  
Author(s):  
Helge Klare ◽  
Jörg M Neudörfl ◽  
Bernd Goldfuss
Keyword(s):  
Hydrogen Bonding ◽  
Catalytic Activity ◽  
High Activity ◽  
Michael Addition ◽  
Bond Activation ◽  
High Catalytic Activity ◽  
Open Chain ◽  
High Hydrogen ◽  
Michael Additions ◽  
Asymmetric Michael Addition

Ten novel hydrogen-bonding catalysts based on open-chain PV-amides of BINOL and chinchona alkaloids as well as three catalysts based on rigid cis-PV-cyclodiphosphazane amides of N 1,N 1-dimethylcyclohexane-1,2-diamine have been developed. Employed in the asymmetric Michael addition of 2-hydroxynaphthoquinone to β-nitrostyrene, the open-chain 9-epi-aminochinchona-based phosphorus amides show a high catalytic activity with almost quantitative yields of up to 98% and enantiomeric excesses of up to 51%. The cyclodiphosphazane catalysts show the same high activity and give improved enantiomeric excesses of up to 75%, thus representing the first successful application of a cyclodiphosphazane in enantioselective organocatalysis. DFT computations reveal high hydrogen-bonding strengths of cyclodiphosphazane PV-amides compared to urea-based catalysts. Experimental results and computations on the enantiodetermining step with cis-cyclodiphosphazane 14a suggest a strong bidentate H-bond activation of the nitrostyrene substrate by the catalyst.

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