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Artículo
Preparation of Chitosan-supported Urea Materials and their Application in Some Organocatalytic Procedures
(Elsevier, 2018)
An efficient and mild procedure was developed for the preparation of three chitosan-supported ureas containing electron-withdrawing groups. These catalysts were characterized and employed as organocatalysts in different ...
Artículo
Bifunctional Squaramide Organocatalysts for the Asymmetric Addition of Formaldehyde tert-Butylhydrazone to Simple Aldehydes
(Wiley-Blackwell, 2018)
The nucleophilic addition of formaldehyde tert-butylhydrazone to simple aldehydes (a formal hetero-carbonyl–ene reaction) can be performed with good reactivity and excellent enantioselectivity by virtue of the dual ...
Artículo
Pyridine–hydrazone ligands in enantioselective palladium-catalyzed Suzuki–Miyaura cross-couplings
(Elsevier, 2016)
The geometries and coordination properties of modular pyridineehydrazone N,N-ligands containing C2- symmetric trans-2,5-diphenylpyrrolidine and trans-2,5-diphenylpiperidine as the terminal dialkylamino units have been ...
Artículo
N-Heterotricyclic Cationic Carbene Ligands. Synthesis, Reactivity and Coordination Chemistry
(Royal Society of Chemistry, 2018)
The direct dialkylation of triazolo[4,3-b]isoquinolin-3-ylidene structures readily affords dicationic N-heterotricyclic azolium salts. These are suitable starting materials for the synthesis of transition metal complexes ...
Artículo
Asymmetric Organocatalytic Synthesis of Fluorinated β-Hydroxy Diazenes
(Wiley-Blackwell, 2019)
The nucleophilic addition of formaldehyde tert-butyl hydrazone to fluoromethyl ketones provides a valuable tool for the synthesis of highly functionalized β-hydroxy β-tri- and difluoromethyl diazenes. Excellent reactivities ...
Artículo
Chirality and catalysis with aromatic N-fused heterobicyclic carbenes
(Royal Society of Chemistry, 2016)
The benzoannulation of the most common families of aromatic NHCs, imidazol-2-ylidenes and 1,2,4-triazol-3-ylidenes, results in heterobicyclic imidazo[1,5-a]pyridin-3-ylidenes (ImPy's) and [1,2,4]triazolo[4,3-a]pyridin-3-ylidenes ...
Artículo
AuI-Catalyzed Haloalkynylation of Alkenes
(Wiley-Blackwell, 2020)
The formal insertion of alkenes into aromatic chloro- and bromoalkynes takes place under cationic gold catalysis. This haloalkynylation reaction can be performed with cyclic, gem-disubstituted and monosubstituted alkenes, ...
Artículo
Axially Chiral Triazoloisoquinolin-3-ylidene Ligands in Gold(I)-catalyzed Asymmetric Intermolecular (4 + 2) Cycloadditions of Allenamides and Dienes
(American Chemical Society, 2012)
The first highly enantioselective intermolecular (4 + 2) cycloaddition between allenes and dienes is reported. The reaction provides good yields of optically active cyclohexenes featuring diverse substitution patterns and ...
Artículo
Solvent-free synthesis of quaternary alpha-hydroxy alpha-trifluoromethyl diazenes: the key step of a nucleophilic formylation strategy
(Royal Society of Chemistry, 2016)
An efficient, scalable and operationally simple one-pot, 2-step strategy for the nucleophilic formylation of trifluoromethyl ketones is presented. The key step is an unprecedented diaza-carbonyl-ene reaction of formaldehyde ...