scholarly journals Ionic Liquids as Precatalysts in the Highly Stereoselective Conjugate Addition of α,β-Unsaturated Aldehydes to Chalcones

2014 ◽  
Vol 20 (43) ◽  
pp. 13889-13893 ◽  
Author(s):  
Linda Ta ◽  
Anton Axelsson ◽  
Joachim Bijl ◽  
Matti Haukka ◽  
Henrik Sundén
Keyword(s):  
Ionic Liquids ◽  
Conjugate Addition ◽  
Unsaturated Aldehydes

ChemInform Abstract: Ionic Liquids as Precatalysts in the Highly Stereoselective Conjugate Addition of α,β-Unsaturated Aldehydes to Chalcones.

ChemInform ◽  
2015 ◽  
Vol 46 (15) ◽  
pp. no-no
Author(s):  
Linda Ta ◽  
Anton Axelsson ◽  
Joachim Bijl ◽  
Matti Haukka ◽  
Henrik Sunden
Keyword(s):  
Ionic Liquids ◽  
Conjugate Addition ◽  
Unsaturated Aldehydes

scholarly journals Reaction of allene esters with Selectfluor/TMSX (X = I, Br, Cl) and Selectfluor/NH4SCN: Competing oxidative/electrophilic dihalogenation and nucleophilic/conjugate addition

2015 ◽  
Vol 11 ◽  
pp. 1641-1648 ◽  
Author(s):  
A Srinivas Reddy ◽  
Kenneth K Laali
Keyword(s):  
Ionic Liquids ◽  
Conjugate Addition ◽  
Nucleophilic Additions ◽  
Product Analysis ◽  
Imidazolium Ionic Liquids ◽  
Presence And Absence ◽  
Competing Pathways

Reaction of benzyl and ethyl allenoates with TMSX (X = I, Br, Cl) and with NH4SCN were investigated in MeCN, DMF, and in imidazolium ionic liquids [BMIM][NTf2] and [BMIM][PF6] as solvent, in the presence and absence of Selectfluor. Comparative product analysis studies demonstrate that the ability of Selectflour to promote oxidative/electrophilic dihalogenation/dithiocyanation with TMSX/NH4SCN (as observed previously for 1-arylallenes) is diminished in allenoates, most significantly in reactions with TMSCl, and essentially disappearing in reactions with NH4SCN, in favor of nucleophilic/conjugate addition. The study underscores the contrasting reactivity patterns in 1-arylallenes and allenoates toward electrophilic and nucleophilic additions in halofunctionalization with TMSX/Selectfluor and thiocyanation reactions with NH4SCN/Selectfluor. These competing pathways are influenced by the nature of the anion, allene structure, and the choice of solvent.

Assessment of non-standard reaction conditions for asymmetric 1,3-dipolar organocatalytic cycloaddition of nitrone with α,β-unsaturated aldehydes

2015 ◽  
Vol 69 (5) ◽  
Author(s):  
Melinda Mojzesová ◽  
Mária Mečiarová ◽  
Ambroz Almássy ◽  
Roger Marti ◽  
Radovan Šebesta
Keyword(s):  
Ionic Liquids ◽  
Flow Reactor ◽  
Dipolar Cycloaddition ◽  
Reaction Conditions ◽  
Experimental Conditions ◽  
Flow Process ◽  
Unsaturated Aldehydes ◽  
Solvent Free Conditions ◽  
Standard Reaction ◽  
Organocatalytic Reactions

AbstractNon-standard experimental conditions can often enhance organocatalytic reactions considerably. The current study explores the effectiveness of a range of non-standard reaction conditions for the asymmetric organocatalytic 1,3-dipolar cycloaddition of a nitrone with α,β-unsaturated aldehydes. The influence of ionic liquids, high-pressure conditions, ultrasound, microwave irradiation and ballmilling was tested as well as the flow process. Because of the low reactivity of the nitrone and unsaturated aldehydes in the 1,3-dipolar cycloaddition, cycloadducts were isolated in only moderate yields from the majority of experiments. However, high diastereo- and enantioselectivities were observed in ionic liquids under solvent-free conditions and in the flow reactor.

ChemInform Abstract: Copper-Catalyzed Conjugate Addition of Trimethylaluminum to α,. beta.-Unsaturated Aldehydes.

ChemInform ◽  
2010 ◽  
Vol 25 (51) ◽  
pp. no-no
Author(s):  
J. KABBARA ◽  
S. FLEMMING ◽  
K. NICKISCH ◽  
H. NEH ◽  
J. WESTERMANN
Keyword(s):  
Conjugate Addition ◽  
Unsaturated Aldehydes

Umpolung of α,β-unsaturated aldehydes by electrogenerated NHCs in ionic liquids: Synthesis of γ-butyrolactones

2011 ◽  
Vol 13 (7) ◽  
pp. 738-741 ◽  
Author(s):  
Monica Orsini ◽  
Isabella Chiarotto ◽  
Michelle M.M. Feeney ◽  
Marta Feroci ◽  
Giovanni Sotgiu ◽  
...  
Keyword(s):  
Ionic Liquids ◽  
Unsaturated Aldehydes

Reactions of CH-acids with  , -unsaturated aldehydes in ionic liquids

2004 ◽  
Vol 53 (3) ◽  
pp. 647-651 ◽  
Author(s):  
G. V. Kryshtal ◽  
G. M. Zhdankina ◽  
I. V. Astakhova ◽  
S. G. Zlotin
Keyword(s):  
Ionic Liquids ◽  
Ch Acids ◽  
Unsaturated Aldehydes
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