This review article presents how nitrogen-centred Lewis bases were modified in order to increase their reactivity in catalytic processes. As examples, we focus on alcohol acylation and Morita-Baylis-Hilman reactions in order to showcase the fundamental parameters at play in transformations initiated by catalysts bearing respectively an active sp(2) or sp(3) nitrogen atoms. These two aspects a...

Novel routes for the preparation of 2-amino-4H-pyran-3-carbonitrile 9, amino-arylbenzoic acid ester derivatives 13a,b, 2-aminotetrahydro-4H-chromene-3-carbonitrile 18, 3-amino-4-cyanotetrahydronaphthalene-2-carboxylic acid ester 26 and 4-amino-3,5-dicyanophthalic acid ester derivatives 37a-c were developed. The synthetic methods utilize one-pot reactions of acetylene carboxylic acid esters, α,β...

By using DABCO·(SO(2))(2), DABSO, as a solid bench-stable SO(2)-equivalent, the palladium-catalysed aminosulfonylation of aryl-, alkenyl- and heteroaryl halides has been achieved. N,N-Dialkylhydrazines are employed as the N-nucleophiles and provide N-aminosulfonamides as the products in good to excellent yields. The reactions are operationally simple to perform, requiring only a slight excess o...

The phototoxic antidiabetes drug gliclazide (1) is photolabile under aerobic conditions and UV-B light. Irradiation of a phosphate buffered solution of 1 under oxygen atmosphere produces two photoproducts. The photochemistry of 1 involves cleavage of the S-N and C(O)-N bonds of the urea unit. Red blood cell lysis photosensitized by 1 was demonstrated. Their photoproducts didn't show this effect...

A series of poly(ethylene glycol) (PEG)-based segmented block copolymers were synthesized with two structurally different hard segments, linear and heterocyclic aliphatic amines. Ionenes via a modified Menshutkin reaction three weight fractions domains (amine rich segment) soft (PEG oligomers). TGA results show that both DABCO-based ionenes thermally stable up to 250 °C. DSC XRD data indicate i...

In this research, firstly, some derivatives of sulfur containing [1,3,4]thiadiazolo[3,2-a]pyrimidin-5-one have been synthesized and then they were used for the synthesis novel 6′-amino-2,9′-dioxo-2′-phenyl-9′H-spiro[indoline-3,8′-pyrano[2,3-d][1,3,4]thiadiazolo[3,2-a]pyrimidine]-7′-carbonitriles via a one-pot three-component condensation reaction 7-hydroxy-2-phenyl-5H-[1,3,4]thiadiazolo[3,2-a]p...

In this work, a new heterogeneous catalyst, comprising gold supported on DABCO-triazole ionic liquid-modified magnetic nanoparticles (Fe3O4@DT-Au), is developed for A3-coupling reaction. This nano-catalyst characterized using different techniques, such as TEM, SEM, SEM-elemental mapping, XRD, XPS, and TGA. Using 0.05 mol% of the three-component reaction amines, aldehydes alkynes efficiently per...

Die Etablierung von Eintopf-Mehrschritt-Protokollen, die verschiedene Arten Katalysatoren kombinieren, ist ein wichtiges Ziel zur Steigerung der Effizienz in modernen organischen Synthese. Insbesondere das hohe Potenzial Biokatalysatoren muss noch ausgeschöpft werden. Basierend auf einer eingehenden mechanistischen Untersuchung eines neuen organokatalytischen Protokolls unter Verwendung zweier ...