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“Anion recognition in water: complexation by uranyl-salophen derivatives and a glimpse of stochastic sensing”
Get PDFUniversità di Roma la Sapienza and IMC-CN
On the mechanism of oxidative esterification of aromatic aldehydes in BMimBF4: the role of electrogenerated NHC
No full textAn electrochemical methodology for the cyclic CO2 "catch and release". The role of the electrogenerated N-heterocyclic carbene in BMIm-BF4
No full textAccording to the property of N-heterocyclic carbenes (NHCs) to yield NHC-CO2 adducts, a solution of NHCs in the parent room temperature ionic liquid (RTIL) as solvent may act as a system able to catch and release carbon dioxide cyclically and in mild conditions. The system has been set up and analyzed via simple electrochemical methodologies. NHCs have been generated by electrolysis of BMIm-BF4 (as solvent and parent of NHC) in the absence of any base and organic solvent. CO2 has been caught and released in every cycle by bubbling of CO2 in the system at 60 °C, heating and stirring at 120 °C, and subsequently cooling down to 60 °C. In a single series of 10 cycles, performed as a preliminary control, the system is able to catch and release 4 mol of CO2 per Faraday consumed in the electrolysis. © 2013 Elsevier Ltd
Stability of electrogenerated 1-butyl-3-methylimidazol-2-ylidene in DMF. Part 2. Role of acid substrates. [1]
No full textThe stability of 1-butyl-3-methylimidazol-2-ylidene (NHC) in N,N-dimethylformammide (DMF) in the
presence of acids was studied by cyclic voltammetry. The NHC was easily obtained by cathodic reduction
of a solution of 1-butyl-3-methylimidazolium salt (BMImX) in DMF. The voltammetric measurements
allowed to determine the NHC presence (and its concentration) in solution, due to the NHC oxidation
peak. Moreover, carrying out the measurements as a function of time, it was possible to determine the
half-life of NHC in DMF containing three different organic acids. The half-life was defined as the time to
halve the NHC concentration (with respect to the initial one) t1/2. It was found that when acetic acid is
present in solution t1/2 is considerably smaller than t1/2 in its absence (15 min vs 69), while in the
presence of 2,6-dimethylphenol and diethyl malonate (weaker acids than the NHCH+) t1/2 is considerably
higher (130 and 140 min vs 69). A hypothesis on the role of BMIm+ and X on the stability of NHC in DMF
containing acids is reported.
The reactivity of the NHC (studied in this paper) was tested in classical base-induced organic reactions,
and the results are in accordance with the voltammetric analysis
NHC-Catalyzed reactions: electrochemical procedure to evaluate the presence of carbene in the ionic liquid BMImBF4
No full textThe double role of ionic liquid BMIM-BF4 precursor of N-heterocyclic carbene and green solvent in the synthesis of esters
No full textAnion Recognition in Water with Use of a Neutral Uranyl-salophen Receptor
No full textA new water-soluble uranyl-salophen complex incorporating two glucose units has been synthesized. This neutral derivative shows noteworthy binding affinity for fluoride in water thanks to the Lewis acid base interaction occurring between the metal and the anion. Such interaction is strong enough to overcome the high hydration enthalpy of fluoride. Moreover this complex effectively binds hydrogen phosphate and exhibits remarkably strong association for nucleotide polyanions ADP(3-) and ATP(4-)
Towards a sustainable electrochemical activation for recycling CO2: synthesis of bis-O-alkylcarbamates from aliphatic and benzyl diamines
No full textThe optimized conditions for the synthesis of bis-O-alkylcarbamates
with activated CO2 are potentially applicable to a sustainable large
scale manufacturing of key precursors for polymeric resins
Rational Drug Delivery: Towards the Synthesis of Monomeric Units for Biocompatible Microparticles
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