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This study investigated two artificial intelligence techniques, Swarm Intelligence(SI) and Artificial Neural Networks(ANN), aiming to overcome the difficulties of simulating complex processes with unknown reactions and intermediates. These techniques are incorporated in reaction modeling via mass balances and reaction kinetic models. The accuracy and the applicability of the resulting models from ANN and SI were compared in the trained semi-batch reactors and the new continuous flow reactors. The ANN-based model is recommended when the extrapolation is unnecessary, and the data is high in volume and variety at the applied space. In this case, no profound reaction knowledge is required. Otherwise, the SI-based model should be employed, which provides detailed information of the target process and is constrained by physical meaning parameters.

A synthesis process for the ionic liquid (IL) 1-butyl-3-methylimidazolium chloride (BMIM.Cl) was developed using a flow microreactor (FMR) in this study. After the reaction rate analysis, the FMR was efficiently designed using computational fluid dynamics simulation, which can shorten the process development time by reducing trial-and-error experimentation. The designed FMR is composed of a V-shaped mixer and a tubular reactor having a millimeter-scale inner diameter. From the viewpoint of process operation and control, reactors with larger inner diameter are basically preferable. The influence of three inner diameters, 0.75, 2.16, and 4.35 mm, that satisfy temperature constraints on product quality, product yield, and production volume was investigated. It was found that as the inner diameter becomes large, the product yield becomes low because the mass transfer approaches the rate-limiting step of the reaction process. To avoid this problem, it was proposed that static mixers should be built in the reac...

Rufinamide is an antiepileptic drug used to treat the Lennox–Gastaut syndrome. It comprises a relatively simple molecular structure. Rufinamide can be synthesized from an organohalide in three steps. Recently we have shown that microreactor flow networks have better sustainability profiles in terms of life-cycle assessment than the respective consecutive processing in a batch. The analysis was based on the results of a single step conversion from batch to continuous mode. An uninterrupted continuous process towards rufinamide was developed, starting from an alcohol precursor, which is converted to the corresponding chloride with hydrogen chloride gas. The chloride is then converted to the corresponding organoazide that yields the rufinamide precursor via cycloaddition to the greenest and cheapest dipolarophile available on the market. The current process demonstrates chemical and process-design intensification aspects encompassed by novel process windows. Single reaction steps are chemically intensified via a wide range of conditions available in a microreactor environment. Meanwhile, the connection of reaction steps and separations results in process-design intensification. With two in-line separations the process consists of five stages resulting in a total yield of 82% and productivity of 9 g h−1 (11.5 mol h−1 L−1). The process minimizes the isolation and handling of strong alkylating or energetic intermediates, while minimizing water and organic solvent consumption.

The photophysical properties of dendrimers with 1,4-dioxo-3,6-diphenylpyrrolo[3,4-c]pyrrole, also known as DPP, as a core were studied. DPP itself has a high quantum yield of fluorescence, as well as a high molar decadic absorption coefficient, e (e = 33 000 L.mol -1 .cm -1 ). The dendrimers, which differ by their substitution pattern, either at the nitrogen (DPPN) or at the carbon (DPPC), are studied in various solvents with different viscosity and solvent-probe interaction and this for several generations and thus varying molecular volume. The stationary measurements show no difference in the absorption and emission spectra for the different generations nor a solvent-effect. Single photon timing is used to determine the fluorescence lifetime, τ. For both dendrimers, the decay curves can be fitted to a monoexponential model. By means of fluorescence depolarization and fluorescence correlation spectroscopy, the hydrodynamic volumes (V h ) are determined. The results for both dendrimers as well as for both techniques are compared. The hydrodynamic radii of DPPN are similar when obtained by FCS compared with anisotropy. When the properties of the different dendrimers are compared, it can be shown that the hydrodynamic volumes of the first generation DPPC dendrimer are much larger compared to V h of the DPPN dendrimers. The volumes for the third generation are comparable for both substitution patterns.

A new method for the synthesis of trialkyl aminophenoltriacetates (APTRA triesters) and the functionalization of these into suitable building blocks for potential fully conjugated low-affinity fluorescent Ca 2 + indicators are described.

Boronic esters incorporated into a poly(vinyl chloride) (PVC)-supported liquid membrane electrodes have displayed an anionic ionophore properties enabling their use in the potentiometric high-throughput screening procedures. These compounds belong to the class of ligands in which the anion recognition process can be explained on the concept of Lewis type acid-base interactions. Membranes containing boronic esters showed fairly good sensitivity for maleate (cis-isomer) in comparison to fumarate anions (trans-isomer). The potentiometric selectivity coefficients of proposed electrodes proved that common anions did not interfered with the maleate anion determination. The influence of structure of the three boronic esters ionophores on generation of potentiometric signal by developed liquid membrane electrodes was shortly discussed.

Oligomers of well-defined length were prepared by a stepwise sequence of Suzuki couplings using brominated 1,4-dioxo-3,6-diphenylpyrrolo[3,4- c ]pyrrole (DPP) derivatives and 1,4-dibromo-2,5-di- n -hexylbenzene as the monomers. The resulting oligomers contained three, five and seven DPP units, respectively, and could be characterized by 1 H NMR spectroscopy. These compounds could be of potential use as new electroluminescent materials.

Sulfide derivatives of diketopyrrolo[3,4-c]pyrrole (SDPPs) were prepared in a one-pot procedure from arylpyrrolinones, isothiocyanates and alkylating agents, and their properties as fluorophores were evaluated.

A small library of 2-oxo-5-(hetero)arylpyrroles was prepared starting from 2,3-dioxo-5-(hetero)arylpyrrolidines. The large synthetic possibilities of these 2-oxopyrroles were investigated. The 2-oxopyrroles offer a large number of possible derivatizations including reactions with electrophiles. The chloroformylation of 2-oxo-5-(hetero)arylpyrroles provides pyrrole carbaldehydes. Some pyrrole carbaldehydes were used to synthesize polycyclic compounds like pyrrolo[3,4- d ]pyridazinones, a thienopyrrole, a pyrrolobenz[1,4]oxazepine, a pyrrolobenzo[1,4]thiazepine, and a pyrrolobenzo[1,4]diazepine. Hereby we showed through a short exploration that the oxopyrroles and analogues are interesting and versatile synthetic building blocks.

Two fluorescent off-on Ca2+ indicators based on APTRA (o-aminophenol-N,N,O-triacetic acid) as low-affinity ligand for Ca2+ and BODIPY(4,4-difluoro-4-bora-3a,4a-diaza-s-indacene) as a fluorophore were synthesized. The new BODIPY-APTRA compounds absorb in the visible spectrum, with absorption maxima from 505 nm to 570 nm, and have fluorescence spectra that span the visible spectrum, with emission maxima ranging from 525 nm to 625 nm dependent on the substituents at the alpha-positions to the nitrogen atoms. The indicators show a large increase of the fluorescence quantum yield upon increasing Ca2+ concentration. The ground-state dissociation constants Kd estimated at 20 degrees C in 100 mM KCl aqueous buffered solution, pH 7.20, for the two complexes with Ca2+ were found to be around 100 microM.