1,3,4,5-Tetrasubstituted pyrazoles can be rapidly and efficiently synthesized in a one-pot, four-step sequence consisting of Sonogashira coupling, addition-cyclocondensation, bromination, and Suzuki coupling. The second and the last step are microwave-assisted, and according to sequential catalysis, no addition of further Pd catalyst is needed for the terminal step. The title compounds show intense blue fluorescence and high quantum yields.

Keywords: C-C coupling / Cyclocondensation / Fluorescence / Microwave reactions / Multi-component reactions / Pyrazoles 3,5-Disubstituted and 1,3,5-trisubstituted pyrazoles are readily synthesized from acyl chlorides, terminal alkynes, and hydrazines by a consecutive one-pot three-component Sonogashira coupling/Michael addition/cyclocondensation sequence in good to excellent yields. These pyrazoles are highly fluorescent, both in solution and in the solid state. Investigation of the electronic properties by UV/Vis and fluo-

Keywords: Benzodiazepines / C-C coupling / Cyclocondensation / Fluorescence / Microwave-assisted reactions / Multicomponent reactions 2,4-Disubstituted benzodiazepines are readily synthesized in good yields from acyl chlorides, terminal alkynes, and benzene-1,2-diamines by a consecutive one-pot, three-component Sonogashira coupling/Michael addition/cyclocondensation sequence. These diazepines display intense solid-state fluorescence, but only weak emission in solution at room temperature. The absorption and emission maxima can be controlled by the substitution pattern. Upon cooling, how-

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New amines for reactive absorption of CO 2 from process gases were investigated in a comprehensive experimental screening. All studied amines are derivates of triacetoneamine and differ only in the substituent of the triacetoneamine ring structure. The amines are abbreviated by the acronym EvA with a consecutive number, designating the derivate. About 50 EvAs were considered in this work from which 26 were actually synthesized and investigated in aqueous solution. The mass fraction of the amines in the unloaded solution was eitherw 0 EvA = 0.05 g/g orw 0 EvA = 0.4 g/g. The following properties were studied: solubility of CO 2 , rate of absorption of CO 2 , liquid-liquid and solid-liquid equilibrium, foaming behavior, dynamic viscosity, and acid constants. The nine most promising EvAs were evaluated with the NoVa short-cut method [1]. The method yields estimates for the specific energy demand and recirculation rate for a given purification task. Two typical purification tasks were considered: the CO 2 -removal from natural gas and from synthesis gas, respectively. Some of the EvAs showed significantly improved performance compared to monoethanolamine (MEA) and a solvent-blend of methyl-diethanolamine and piperazine (MDEA/PZ).