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In the context of the separation of uranium and plutonium from spent fuel allowed by N,N -dialkylamides, three regioisomers of N,N -di(2-ethylhexyl) butyramide (DEHBA or ββ) and the diastereopure isomers of N -(2-ethylhexyl)- N -(oct-3-yl)butyramide (EHOBA or αβ) were synthesized to assess their extraction performance and to study the mechanisms at the origin of the differences observed between the stereo- and regioisomers. The N,N -dialkylamides showed differences in extraction, with a greater effect of regio- than stereoisomerism. A mechanistic study at both the molecular and supramolecular scales was initially applied to explain these effects. X-ray absorption and UV-vis spectroscopy showed that uranium is extracted by a UO 2 (NO 3 ) 2 L 2 complex, which is not very sensitive to steric hindrance, while plutonium is extracted by two complexes, Pu(NO 3 ) 4 L 2 and Pu(NO 3 ) 6 (HL) 2 , which are differently affected by stereo- and regioisomerism. Investigations at the supramolecular scale also showed that Pu(NO 3 ) 4 L 2 complexes are disadvantaged by the bulkiness of the extractants, while Pu(NO 3 ) 6 (HL) 2 is favored by the preformation of larger supramolecular aggregates.

Silica-based porous liquids (PLs) are innovative and versatile liquid materials with a high potential, although their application is often restricted to gas sorption. In this work, we propose to evaluate their potential to extract metals. For this goal, we have adapted their synthesis to provide PLs functionalized with thiols that are expected to chelate metallic contaminants, such as lead. As the accessibility of liquids and metals to the PL's porous network is one of the key points for their application, we developed an original small-angle neutron scattering experiment to verify that the PL is permeable to polar liquids. Then, preliminary extraction tests have successfully been carried out, with an extraction of lead cations by complexation on one-third of accessible thiol groups. This work demonstrates that the extraction of metal species by a PL is possible and opens many perspectives for optimization.

Developing greener hydrometallurgical processes implies offering alternatives to conventional solvents used for liquid-liquid extraction (LLE) of metals. In this context, it is proposed to substitute the organic phase by a hydrophobic silica-based porous liquid (PL). Two different sulfonated hollow silica particles (HSPs) are modified with various polyethoxylated fatty amines (EthAs) forming a canopy that provides both the targeted hydrophobicity and liquefying properties. This study shows that these properties can be tuned by varying the number of ethylene oxide units in the EthA: middle-range molecular weight EthAs allow obtaining a liquid at room temperature, while too short or too long EthA leads to solid particles. Viscosity is also impacted by the density and size of the silica spheres: less viscous PLs are obtained with small low-density spheres, while for larger spheres (c.a. 200 nm) the density has a less significant impact on viscosity. According to this approach, hydrophobic PLs are successfully synthesized. When contacted with an aqueous phase, the most hydrophobic PLs obtained allow a subsequent phase separation. Preliminary extraction tests on three rare earth elements have further shown that functionalization of the PL is necessary to observe metal extraction., (© 2023 The Authors. Advanced Science published by Wiley-VCH GmbH.)

This study presents a comprehensive investigation of the aggregation behavior of a malonamide extractant molecule ( N , N '-dimethyl, N , N '-dioctylhexylethoxymalonamide (DMDOHEMA)) in three different solvents, including two piperidinium- and (trifluoromethylsulfonyl)imide-based ionic liquids (1-ethyl-1-butylpiperidinium bis(trifluoromethylsulfonyl)imide ([EBPip + ][NTf 2 - ]) and 1-ethyl-1-octylpiperidinium bis(trifluoromethylsulfonyl)imide ([EOPip + ][NTf 2 - ])) and n -dodecane. By combining polarizable molecular dynamics simulations and small-angle X-ray scattering experiments, we extensively investigated the arrangement of supramolecular assemblies of the extractant molecules. Our results showed that the insertion of the alkyl chains of the extractant molecules into the apolar domain of [EOPip + ][NTf 2 - ] has a significant impact on the aggregation behavior of the extractant molecules, leading to the formation of smaller aggregates having a higher dispersion compared to other solvents. These findings provide new insights into the physicochemical properties of this type of system and are crucial in designing more effective solvents for rare earth metal extraction.

Invited for this month's cover is the collaborating group of Dr Guilhem Arrachart and Dr Stéphane Pellet-Rostaing at Institut de Chimie Séparative de Marcoule (ICSM). The cover picture shows a person going uranium fishing thanks to the use of bis-catecholamide materials. These materials have shown interesting performance for the recovery of uranium in saline environments such as seawater. More information can be found in the Research Article by G. Arrachart, S. Pellet-Rostaing, and co-workers., (© 2023 Wiley-VCH GmbH.)

Efficient and selective extractions of precious and critical metal ions such as Au(III) and Pd(II) were investigated using zirconia nanoparticles surface modified with different organic mono- and di-carbamoyl phosphonic acid ligands. The modification is made on the surface of commercial ZrO 2 that is dispersed in aqueous suspension and was achieved by optimizing the Bronsted acid-base reaction in ethanol/H 2 O solution (1:2), resulting in inorganic-organic systems of ZrO 2 -L n (L n : organic carbamoyl phosphonic acid ligand). The presence, binding, amount, and stability of the organic ligand on the surface of zirconia nanoparticles were confirmed by different characterizations such as TGA, BET, ATR-FTIR, and 31 P-NMR. Characterizations showed that all the prepared modified zirconia had a similar specific surface area (50 m 2 .g -1 ) and the same amount of ligand on the zirconia surface in a 1:50 molar ratio. ATR-FTIR and 31 P-NMR data were used to elucidate the most favorable binding mode. Batch adsorption results showed that (i) ZrO 2 surface modified with di-carbamoyl phosphonic acid ligands had the highest adsorption efficiency to extract metals than mono-carbamoyl ligands, and (ii) higher hydrophobicity of the ligand led to better adsorption efficiency. The surface-modified ZrO 2 with di-N,N-butyl carbamoyl pentyl phosphonic acid ligand (ZrO 2 -L 6 ) showed promising stability, efficiency, and reusability in industrial applications for selective gold recovery. In terms of thermodynamic and kinetic adsorption data, ZrO 2 -L 6 fits the Langmuir adsorption model and pseudo-second-order kinetic model for the adsorption of Au(III) with maximum experimental adsorption capacity q max = 6.4 mg.g -1 .

Surfactants aggregate in water into micelles, and these micelles incorporate organic substances to solubilize them. Hydrotropes are compounds that increase the solubility of hydrophobic substances in water without this form of aggregation. Decreasing the chain length of the classical surfactant Aerosol OT (AOT) from C8 to C5 results in a molecule with intermediate properties. Molecular dynamics simulations and surface tension measurements are performed on this short chain derivative of AOT. This compound shows high solubility and at the same time progressive weak aggregation. The hydration of head groups hinders significant plunging into a hydrophobic core, which leads to well defined liquid chain nanodomains. The transition to bicontinuous aggregates is in the concentration range of 1 mol L -1 . The sulfonate group of the head groups (placed at the water interface of worm-like aggregates) rather than the aggregate-aggregate interaction is responsible for the unusual small angle X-ray scattering pattern.

The nanoscale organization of some classes of ionic liquids is responsible for their singular properties. In this paper, we use polarizable molecular dynamics simulations and small-angle X-ray scattering to probe the structure of two piperidinium- and (trifluoromethylsulfonyl)imide-based ionic liquids ([EBPip + ][NTf 2 - ] and [EOPip + ][NTf 2 - ]) that differ in the alkyl chain length of their cation. The X-ray scattering intensities calculated numerically, from the radial distribution functions, are in excellent agreement with the experimental data. The analysis of the different contributions of the X-ray scattering data allowed us to highlight the correlations responsible for the low q peak observed for the long-chain alkyl cations. New angular analyses showed that anions were more likely to align with alkyl chains as their size increased, inducing angular correlation between anions at larger distances. They also showed that the long alkyl chains of the cations aligned more with each other than the short ones. These more aligned alkyl chains induce a smaller volume of the apolar microdomains compared to the well-studied imidazolium-based ionic liquids, leading to the smaller correlation distance for piperidinium-based ionic liquids.

Rare-earth elements (REEs) are involved in most high technology devices and have become critical for many countries. The progress of processes for the extraction and recovery of REEs is therefore essential. Liquid-solid extraction methods are an attractive alternative to the conventional solvent extraction process used for the separation and/or purification of REEs. For this purpose, a solid-phase extraction system was investigated for the extraction and valorization of REEs. Ion-exchange resins were synthesized involving the condensation of terephthalaldehyde with resorcinol under alkaline conditions. The terephthalaldehyde, which is a non-hazardous aromatic dialdehyde, was used as an alternative to formaldehyde that is toxic and traditionally involved to prepare phenolic ion-exchange resins. The resulting formaldehyde-free resole-type phenolic resins were characterized and their ion-exchange capacity was investigated in regard to the extraction of rare-earth elements. We herein present a promising formaldehyde and phenol-free as a potential candidate for solid-liquid extraction REE with a capacity higher than 50 mg/g and the possibility to back-extract the REEs by a striping step using a 2 M HNO 3 solution.

The phase transfer of ions is driven by gradients of chemical potentials rather than concentrations alone (i.e., by both the molecular forces and entropy). Extraction is a combination of high-energy interactions that correspond to short-range forces in the first solvation shell such as ion pairing or complexation forces, with supramolecular and nanoscale organization. While the latter are similar to the long-range solvent-averaged interactions in the colloidal world, in solvent extraction they are associated with lower characteristic lengths of the nanometric domain. Modeling of such complex systems is especially complicated because the two domains are coupled, whereas the resulting free energy of extraction is around k B T to guarantee the reversibility of the practical process. Nevertheless, quantification is possible by considering a partitioning of space among the polar cores, interfacial film, and solvent. The resulting free energy of transfer can be rationalized by utilizing a combination of terms which represent strong complexation energies, counterbalanced by various entropic effects and the confinement of polar solutes in nanodomains dispersed in the diluent, together with interfacial extractant terms. We describe here this ienaics approach in the context of solvent extraction systems; it can also be applied to further complex ionic systems, such as membranes and biological interfaces.

Based on silica hollow nanospheres grafted with an ionic shell, silica-based type I porous liquids remain poorly exploited, despite their huge versatility. We propose here to explore the main synthesis step of these promising materials with a thorough characterization approach to evaluate their structural and porous properties. Modifying the main synthesis parameter, the mechanism of the spheres' formation is clarified and shows that the calcination temperature, the surfactant concentration as well as the micelle swelling agent concentration allow tuning not only the size of the nanospheres and internal cavities, but also the silica shell microporosity and, therefore, the accessibility of the internal cavities. This study highlights the key parameters of hollow silica nanospheres, which are at the basis of type I porous liquids synthesis with optimized structural and porous properties.

Separation processes based on room temperature ionic liquids (RTIL) and electrochemical refining are promising strategies for the recovery of lanthanides from primary ores and electronic waste. However, they require the speciation of dissolved elements to be known with accuracy. In the present study, Eu coordination and Eu III /Eu II electrochemical behavior as a function of water content in 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIm][NTf 2 ]) was investigated using UV-visible spectrophotometry, time-resolved laser fluorescence spectroscopy, electrochemistry, and X-ray absorption spectroscopy. In situ measurements were performed in spectroelectrochemical cells. Under anhydrous conditions, Eu III and Eu II were complexed by NTf 2 , forming Eu-O and Eu-(N,O) bonds with the anion sulfoxide function and N atoms, respectively. This complexation resulted in a greater stability of Eu II , and in quasi-reversible oxidation-reduction with an E 0 ' potential of 0.18 V versus the ferrocenium/ferrocene (Fc + /Fc) couple. Upon increasing water content, progressive incorporation of water in the Eu III coordination sphere occurred. This led to reversible oxidation-reduction reactions, but also to a decrease in stability of the +II oxidation state (E 0 '=-0.45 V vs. Fc + /Fc in RTIL containing 1300 mm water)., (© 2020 Wiley-VCH GmbH.)

Phase modifiers are often added to solvent extraction processes to avoid the third-phase formation. While this important issue was attributed to sticky interactions between reverse aggregates, structural effects of phase modifiers remain ambiguous. As they are similar to reverse hydrotropes, phase modifiers may act as cosurfactants or cosolvents in the organic phase in a solvent extraction system. We therefore applied an innovative small-angle scattering approach coupled with surface tension measurements on the industrially applied AMEX process to evaluate how phase modifiers repel the third phase and affect the extraction properties. We first confirmed that adding 1-octanol has a small influence on the extraction performance. By varying the scattering contrast of the solution with deuterated 1-octanol, we found that 1-octanol is located both in the solvent, acting as a cosolvent and diluting the aggregates, and in an outer shell of the aggregates. Further surface tension measurements demonstrated that instead of penetrating till the core of the aggregates as a cosurfactant, 1-octanol only penetrates their shell and forms a shielding barrier avoiding the coalescence of aggregates.

Knowledge of the complex microstructure in solvent extraction phases is mandatory for a full comprehension of ionic separation. Coupling EXAFS with MD simulations for uranyl extraction in sulfuric media with tertiary amine extractants enabled unravelling of the unprecedented uranyl tri-sulfate structure.

Soft matter structuring is a useful tool for the preparation of well-structured inorganic materials. Here, we report a strategy using a structured solvent based on binary mixtures as a directing agent for silica nanoparticles in aerogel elaboration. Binary mixtures involving water/ethanol and water/ tert-butanol have been respectively chosen as representatives of unstructured and structured solvents. The water/alcohol/TEOS systems were effectively characterized as surfactant-free microemulsions. The enhanced solvent structuring, however, disappears upon the reaction with TEOS, and assembly is directed by solvent structuring found in the binary mixtures. For the first time, the influence of solvent composition on the sol-gel reaction was investigated with respect to the reaction rate and the structuring behavior thanks to dynamic light scattering (DLS), small- and wide-angle X-ray scattering (SWAXS), and transmission electron microscopy (TEM) experiments. The silica nanoparticles aggregate in a different manner depending on the solvent composition, which allows the change in the morphology, the degree of interconnection, and the surface area of the resulting material. Silica nanoparticles with a very high surface area of up to 2000 m 2 /g can be obtained by this approach.

The selective extraction of uranium by N-octylcalix[4]azacrown (NOCAC) and N-ethylhexylcalix[4]azacrown (NEHCAC) was investigated. The ligands were synthesised in three steps through the functionalisation of t-butyl calix[4]arene at the distal-1,3-positions of the lower rim with ethyl acetate groups followed by cyclisation with (imino)bis(ethane-2,1-diyl)diamide. A detailed investigation on the effect of various parameters, such as the aqueous phase acidity (sulfuric acid), the ionic strength, and ligand concentration, on the extraction of uranium(vi) has been conducted. The effect of the H2SO4 concentration has been studied from 0.02 to 3 M. Preliminary studies carried out on NOCAC in dodecane/octanol diluents showed that the uranium extraction from sulfuric acid is more efficient at a low H2SO4 concentrations. The stoichiometry of complexation was estimated from the slope method, NMR titration, and electrospray ionisation-mass spectrometry analysis. Both ligands were found to be highly selective for uranium(vi) over other competitive cations present in a simulated leach solution containing seven competitive cations. The successful recovery of the uranium from the organic phase has been performed thanks to stripping steps involving ammonium oxalate, ammonium carbonate, and sodium carbonate as stripping agents.

We show that three different morphologies exist near the two-phase boundary of ternary systems containing a hydrotropic cosolvent. Based on synchrotron small- and wide-angle X-ray scattering combined with molecular dynamics, we rationalize the specific scattering signature of direct, bicontinuous, and reverse mesoscale solubilization. Surprisingly, these mesostructures are resilient toward strong acids, which are required in industrial applications. However, on a macroscopic scale, the phase boundary shifts in salting-in and salting-out in the direct and respectively reverse regime, leading to a crossing of the binodals.

The self-assembly of amino-undecyl-triethoxysilane (AUT) as micelles in water is considered. The behavior of acid/AUT systems is governed by a complete proton transfer from the acid to the amine, leading to the formation of an ammonium headgroup. This moiety is responsible for the bending of the interface between the organic core of the micelles and the surrounding water. By playing with the size of the acid used as curvature agent, the amphiphilic behavior of the organosilane molecule may be adjusted. We follow the aggregation as the curvature agent size increases. This approach constitutes an efficient and original method in order to tune the nanostructure of highly functionalized silica at the early stage of the elaboration. Small-angle X-ray scattering, wet scanning transmission electron microscopy, dynamic light scattering, and complementary characterization techniques indicate that hybrid organic-inorganic planar objects and vesicles are obtained for smaller curvature agents. Increasing the size of the curvature agent results in a transition of the aggregation geometry from vesicles to cylindrical direct micelles, finally leading to nanofibers organized in a 2D hexagonal network resembling a "reverse MCM-41 structure". A geometrical molecular self-assembly model is finally proposed, considering the dimensions of the surfactant tail and those of the head groups.

An innovative and straightforward synthesis of second-generation 2-arylbenzo[b]thiophenes as structural analogues of INF55 and the first generation of our laboratory-made molecules was developed. The synthesis of C2-arylated benzo[b]thiophene derivatives was achieved through a method involving direct arylation, followed by simple structural modifications. Among the 34 compounds tested, two of them were potent NorA pump inhibitors, which led to a 16-fold decrease in the ciprofloxacin minimum inhibitory concentration (MIC) against the SA-1199B strain at concentrations of 0.25 and 0.5 μg mL(-1) (1 and 1.5 μm, respectively). This is a promising result relative to that obtained for reserpine (MIC=20 μg mL(-1)), a reference compound amongst NorA pump inhibitors. These molecules thus represent promising candidates to be used in combination with ciprofloxacin against fluoroquinolone-resistant strains., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We show in the case of N,N'-dimethyl-N,N'-dioctyl-2-(2(hexyloxy)ethyl)-malonamide (DMDOHEMA) chosen as a typical oil-soluble extractant with surface activity that the free energy of formation of reverse micelles in the solvent phase strongly depends on the presence of polar solutes. Free energies per molecule vary typically from 0 to 2 kT per molecule (5 kJ mol(-1)), depending on the kosmotropic/chaotropic nature of the anion extracted. Variations of the reverse aggregation free energy introduced by acids and other co-extracted solutes as deduced from the critical aggregation concentrations cannot be neglected while modelling extraction. With typical aggregation numbers of 4-6, the free energy of formation of one reverse aggregate varies up to 20 kJ mol(-1), which is four times the typical difference in free energy of one single cation transfer between a "target" and a non-target ion in practical extraction and stripping industrial processes.

Chronic kidney disease (CKD) is associated with numerous metabolic and endocrine disturbances, including abnormalities of calcium and phosphate metabolism and an inflammatory syndrome. The latter occurs early in the course of CKD and contributes to the development and progression of vascular calcification. A few therapeutic strategies are today contemplated to target vascular calcification in patients with CKD: vitamin K2, calcimimetics and phosphate binders. However, none has provided complete prevention of vascular calcification and there is an urgent need for alternate efficient treatments. Recent findings indicate that tissue-nonspecific alkaline phosphatase (TNAP) may represent a very promising drug target due to its participation in mineralization by vascular smooth muscle cells. We report the synthesis of four levamisole derivatives having better inhibition property on TNAP than levamisole. Their IC50, Ki and water solubility have been determined. We found that the four inhibitors bind to TNAP in an uncompetitive manner and are selective to TNAP. Indeed, they do not inhibit intestinal and placental alkaline phosphatases. Survival MTT tests on human MG-63 and Saos-2 osteoblast-like cells have been performed in the presence of inhibitors. All the inhibitors are not toxic at concentrations that block TNAP activity. Moreover, they are able to significantly reduce mineralization in MG63 and Saos-2 osteoblast-like cells, indicating that they are promising molecules to prevent vascular calcification., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

A series of redox-responsive architectures featuring two bipyridinium units introduced onto the lower rim of a calixarene skeleton has been synthesized. The redox-triggered intramolecular dimerization of the reduced bipyridiniums has been investigated by electrochemistry, spectroelectrochemistry and by theoretical chemistry. The spectroscopic signature of the intramolecular dimers was found to evolve significantly with the size of the alkyl linker introduced between the calixarene skeleton and the bipyridinium units. On account of experimental data supported by theoretical calculations, these differences have been attributed to the extent of the orbital overlap in the π-dimerized species, involving either four or only two of the pyridine rings of the bipyridinium radical cations stacked in eclipsed or staggered conformations, respectively.

Pathological calcifications induced by deposition of basic phosphate crystals or hydroxyapatite (HA) on soft tissues are a large family of diseases comprising of ankylosing spondylitis (AS), end-stage osteoarthritis (OA) and vascular calcification. High activity of tissue non-specific alkaline phosphatase (TNAP) is a hallmark of pathological calcifications induced by HA deposition. The use of TNAP inhibitor is a possible therapeutic option to address calcific diseases produced by HA deposition on soft tissues. We report the synthesis of a series of thiopheno-imidazo[2,1-b]thiazole derivatives which were evaluated as potential inhibitors of TNAP displaying a large range of IC(50) at pH 10.4 (from 42±13 μM to more than 800 μM)., (Copyright © 2011. Published by Elsevier Ltd.)

Presence of basic calcium phosphate in knee joints of osteoarthritis patients could be prevented by inhibiting tissue non-specific alkaline phosphatase (TNAP) activity. Levamisole or the L stereoisomer of tetramisole (a known TNAP inhibitor) has been used as a treatment for curing rheumatoid arthritis but its therapeutical use is limited due to side effects. We report the synthesis and the TNAP inhibition property of benzo[b]thiophene derivatives, among which benzothiopheno-tetramisole and benzothiopheno-2,3-dehydrotetramisole, which could be involved in a drug therapy for osteoarthritis. Two water soluble racemic benzothiopheno-tetramisole and -2,3-dehydrotetramisole with apparent inhibition constants K(i)=85+/-6 microM and 135+/-3 microM (n=3) comparable to that of enantiomeric levamisole 93+/-4 microM were found. Several novel derivatives showed more pronounced inhibition properties towards intestinal alkaline phosphatase than TNAP.

A selective palladium-catalyzed arylation and heteroarylation of 8-oxo-5,6,7,8-tetrahydroindolizines has been developed. Mechanistic studies assume an electrophilic substitution pathway for this transformation. This method provides an efficient one-step synthesis of 3-aryl-8-oxo-5,6,7,8-tetrahydroindolizines.

A library of bisphosphonate-based ligands was prepared using solution-phase parallel synthesis and tested for its uranium-binding properties. With the help of a screening method, based on a chromophoric complex displacement procedure, 23 dipodal and tripodal chelates bearing bisphosphonate chelating functions were found to display very high affinity for the uranyl ion and were selected for evaluation of their in vivo uranyl-removal efficacy. Among them, 11 ligands induced a huge modification of the uranyl biodistribution by deviating the metal from kidney and bones to liver. Among the other ligands, the most potent was the dipodal bisphosphonate 3C which reduced the retention of uranyl and increased its excretion by around 10% of the injected metal.

The synthesis based on palladium catalytic coupling of 38 new-arylated benzo[b]thiophenes or thiophenes is described in a few steps. We also report the direct arylation of the position 3 of the benzo[b]thiophenic structure, a 'one pot' 2,5-heterodiarylation of thiophenes as well as the synthesis of precursors of amino-acids with a 2-arylated benzo[b]thiophene core. These compounds were evaluated on bacteria strains: most of them did not exhibit any antibiotic activity but were found to selectively inhibit the NorA multidrug transporter of Staphylococcus aureus. As such, they restored the activity of the NorA substrates ciprofloxacin against a resistant S. aureus strain in which this efflux pump is over-expressed.

Some (1,3')-bis-tetrahydroisoquinolines were reported as scaffold intermediates for the synthesis of pentacyclic piperazine core alkaloids and their cytotoxicity against cancerous cell lines was evaluated. The NMR and X-ray structural assignments revealed an anti C3-C11 backbone stereochemistry of piperazine structures. Inhibition of cancer cell proliferation of (1,3')-bis-tetrahydroisoquinoline scaffolds and pentacyclic piperazine systems was assessed against three human cancer cell lines (K562 myelogenous leukemia, A549 lung carcinoma, MCF-7 breast adenocarcinoma) and both mouse tumor cell lines of blood (P388) and lymphocytic (L1210) leukemia with considerable activity against the latter. The cell cycle analysis was also studied by flow cytometry measurement on K562 cell line.

[reaction: see text] Benzo[b]thiophene derivatives are important in part because of their use as selective estrogen receptor modulators. They are usually synthesized by intramolecular cyclization. Here, we propose a method for the synthesis of 2-arylbenzo[b]thiophenes with heteroatoms at the 3-positions directly from the benzo[b]thiophene core by using an aromatic nucleophilic substitution reaction and Heck-type coupling. This methodology provides 2-aryl-3-amino or phenoxybenzo[b]thiophenes in about 35% overall yield in 5 steps.