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Chiral diphosphines with a biphenyl bridge and the chirality borne by the phosphorus atoms and not due to the atropoisomery of the biaryl backbone have been scarcely studied. Herein, we report the asymmetric synthesis of the ( S , S )-2,2'-bis(ferrocenylphenylphosphino)biphenyl (BipheP Fc *) ligand and its application in Rh-catalyzed hydrogenation. The synthesis was based on the enantioselective preparation of P-chirogenic ferrocenyl( o -bromophenyl)phenylphosphine by the reaction of sec -phosphine-borane with 1,2-dibromobenzene and its homocoupling into BipheP Fc *. Hydrogenations catalyzed by the Rh/BipheP Fc * complex led to enantioselectivities of ≤96%.

Positron Emission Tomography (PET) is used in oncology for tumor diagnosis, commonly relying on fluorine-18 ( 18 F) emission detection. The conventional method of 18 F incorporation on to probes by covalent bonding is harsh for sensitive biomolecules, which are nonetheless compounds of choice for the development of targeted probes. This study explores gallium- 18 F (Ga 18 F) coordination, a milder alternative method occurring in aqueous media at the final stage of radiosyntheses. Pyclen-based chelating agents were proposed to capture (GaF) species at room temperature and pH≥5 making the radiofluorination process compatible with heat- and acid-sensitive biomolecules. Highly promising results were obtained with the PC2A-based chelating agent LH 2 derived from the new bifunctional PC2A-OAE-NCS compound. The solid-state structure of GaF(L) was elucidated by X-ray diffraction and revealed an unconventional heptacoordination of Ga(III). A high radiochemical conversion (RCC) of 86 % was achieved at room temperature, in water at pH 5 within 20 minutes. Stability studies showed the robustness of the GaF(L) complex in aqueous media for at least one day and at least one hour for the radiolabeled analog Ga 18 F(L). These findings demonstrated that PC2A-based compounds are chelating agents of choice for (Ga 18 F) species, suggesting a real technological breakthrough for PET imaging and precision medicine., (© 2024 The Author(s). Chemistry - A European Journal published by Wiley-VCH GmbH.)

The structure of pinaverium bromide (systematic name: 4-[(2-bromo-4,5-di-meth-oxy-phen-yl)meth-yl]-4-{2-[2-(6,6-dimethyl-2-bi-cyclo-[3.1.1]hepta-nyl)eth-oxy]eth-yl}morpholin-4-ium bromide; C 26 H 41 Br 2 NO 4 ), was determined at 110 K. It has monoclinic ( P 2 1 ) symmetry. It is of inter-est with respect to its anti-inflammatory properties. The asymmetric unit contains two independent mol-ecules, one of which exhibits disorder of the bi-cyclo terminal group (occupancy factors: 0.78 and 0.22)., (© Rousselin and Clavel 2024.)

An enantioselective synthesis of a new class of benzophosphole-based heterocycles bearing a fused triazole ring with enantioselectivities of ≤99% is reported. The key steps of the synthesis are based on an innovative stereospecific phosphinyl N → O migration of aminophosphine-boranes into phosphinites, followed by an intramolecular cyclization. Five X-ray structures of P-chirogenic triazolobenzophospholes and a gold(I) complex were established, for assigning absolute configurations, the stereochemistry of the reactions, and the placement of the triazole substituent at the syn position of the P center.

Phlorins have long remained underexplored relative to their fully conjugated counterparts, such as porphyrins, hydroporphyrins, and corroles. Herein, we have attempted to bridge that knowledge gap with a scalar-relativistic density functional theory (DFT) study of unsubstituted iridium and gold phlorin derivatives and a multitechnique experimental study of iridium-bispyridine and gold complexes of 5,5-dimethyl-10,15,20-tris(pentafluorophenyl)phlorin. Theory and experiments concur that the phlorin derivatives exhibit substantially smaller HOMO-LUMO gaps, as reflected in a variety of observable properties. Thus, the experimentally studied Ir and Au complexes absorb strongly in the near-infrared (NIR), with absorption maxima at 806 and 770 nm, respectively. The two complexes are also weakly phosphorescent with emission maxima at 950 and 967 nm, respectively. They were also found to photosensitize singlet oxygen formation, with quantum yields of 40 and 28%, respectively. The near-infrared (NIR) absorption and emission are consonants with smaller electrochemical HOMO-LUMO gaps of ∼1.6 V, compared to values of ∼2.1 V, for electronically innocent porphyrins and corroles. Interestingly, both the first oxidation and reduction potentials of the Ir complex are some 600 mV shifted to more negative potentials relative to those of the Au complex, indicating an exceptionally electron-rich macrocycle in the case of the Ir complex.

Recent advances in visible light photocatalysis represent a significant stride towards sustainable catalytic chemistry. However, its successful implementation in fine chemical production remains challenging and requires careful optimization of available photocatalysts. Our work aims to structurally modify bioinspired porphyrin catalysts, addressing issues related to their laborious synthesis and low solubility, with the goal of increasing their efficiency and developing reusable catalytic systems. We have demonstrated the catalytic potential of readily available meso -tetrakis[4-(diethoxyphosphoryl)phenyl]porphyrins (M(TPPP)). Novel metal (Pd(II), Co(II) and In(III)) complexes with this ligand were prepared in good yields. These chromophores were characterized in solution using spectroscopic (NMR, UV-vis, fluorescence) and electrochemical methods. The introduction of phosphonate groups on the phenyl substituents of meso -tetraphenylporphyrins (M(TPP)) improves solubility in polar organic solvents without significantly altering the photophysical properties and photostability of complexes. This structural modification also leads to easier reductions and harder oxidations of the macrocycle for all investigated complexes compared to the corresponding TPP derivatives. The free base porphyrin, zinc(II), palladium(II), and indium(III) complexes were studied as photocatalysts for oxidation of sulfides to sulfoxides using molecular oxygen as a terminal oxidant. Both dialkyl and alkyl aryl sulfides were quantitatively transformed into sulfoxides under blue LED irradiation in the acetonitrile-water mixture (10 : 1 v/v) with a low loading (0.005-0.05 mol%) of porphyrin photocatalysts, where H 2 (TPPP) and Pd(TPPP) were found to be the most efficient. The reaction mechanism was studied using photoluminescence and EPR spectroscopies. Then, to access reusable catalysts, water-soluble derivatives bearing phosphonic acid groups, H 2 (TPPP-A) and Pd(TPPP-A), were prepared in high yields. These compounds were characterized using spectroscopic methods. Single-crystal X-ray diffraction analysis of Pd(TPPP-A) reveals that the complex forms a 3D hydrogen-bonded organic framework (HOF) in the solid state. Both H 2 (TPPP-A) and Pd(TPPP-A) were found to catalyze the photooxidation of sulfides by molecular oxygen in the acetonitrile-water mixture (1 : 1 v/v), while only Pd(TPPP-A) resulted in selective production of sulfoxides. The complex Pd(TPPP-A) was easily recovered through extraction in the aqueous phase and successfully reused in five consecutive cycles of the sulfoxidation reaction.

Poly(vinyl chloride) undergoes dechlorination in the presence of triethylsilane (Et 3 SiH) and a catalytic amount of [Cp 2 Zr(NPh 2 )][CH 3 B(C 6 F 5 ) 3 ] (1 b) at 40-80 °C, with up to 91 % efficiency. Stoichiometric reactivity studies conducted on cyclohexyl chloride as a model suggest that 1 b dechlorinates PVC by initial chloride abstraction, followed by hydride transfer to the cationic PVC chain from Et 3 SiH. Consumer items such as pipe fitting, vinyl disc or electric cable insulation undergo either dechlorination or hydrosilylation of the carbonyl-containing copolymer (polyvinyl acetate) or plasticizer (phthalate)., (© 2024 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

In the recent past, the chirality borne by a phosphorus center has aroused growing interest in many fields, and the development of new methodologies, notably using inexpensive reagents and simple experimental conditions, has become topical. An efficient stereoselective synthesis of P-chirogenic phosphinites useful as chiral phosphorus building blocks is herein described thanks to a new intramolecular phosphorus rearrangement based on P*(III)-phosphinyl N→O migration. This rearrangement was performed by heating at 50 °C aminophosphine-boranes, easily prepared from chiral amino alcohols, with DABCO in toluene overnight. Twenty-seven P-chirogenic phosphinites and borane complexes were thus prepared in yields up to 89%. The crude P*(III)-phosphinites were in situ used in stereoselective synthesis of P-chirogenic aminophosphine-phosphinites, phosphinothioates, sec - and tert -phosphine-oxides, and mono- and diphosphines in overall yields ranging from 28 to 89% and with e.e. up to 99%. Twenty-one X-ray structures of P-chirogenic compounds were established, allowing us to attribute undoubtedly their absolute configuration and the stereochemistry of the reactions. Finally, new ferrocenyl-bridged diphosphine ligands synthesized from P*(III)-chirogenic diphosphinites were tested in asymmetric metal-catalyzed reactions, providing enantioselectivities up to 95% e.e. in allylation of α-naphthylmethylamine at room temperature. To conclude, this rearrangement opens up an efficient new way for the stereoselective synthesis of numerous classes of P-chirogenic phosphorus compounds, notably bearing bulky substituents.

We report the synthesis of a new generation of phenoxy-amidine ligands based on an aryloxy moiety possessing an ortho-N -linked trisubstituted amidine. The reaction of the phenol-amidine proligands with aluminum and zinc alkyls gave mono- or bis-ligated complexes depending on the metal/ligand ratio used. The solid-state structure of four proligands and thirteen Zn and Al complexes has been determined by X-Ray diffraction analysis. The mono-ligated complexes present an aryloxy-bridged dimeric structure, which is retained in solution in the case of Zn complexes but not with aluminum according to DOSY NMR experiments. Bis(ligated) Al and Zn complexes exhibit fluxional behaviour in solution attributed to coordination-decoordination of the amidine moiety and the rotation around the amidine C-NR' 2 and C-Ar bonds. These complexes were tested for the ROP of rac -lactide in solution and under bulk conditions. In both cases, the most performant catalysts are Zn complexes featuring a phenoxy-amidine ligand with a pendant additional dimethylamino arm.

Ethylene- and phenylene-bridged bis(salicylamidine) ligands have been readily prepared from ethylene or phenylenediamine and iminium chloride derivatives generated in situ from N , N -dialkylsalicylamides. The former, in its diprotonated form (FAlenH 2 ), reacts with AlMe 3 to afford a zwitterionic dimethyldiphenoxyaluminate complex with the FAlen ligand monoprotonated and in a bidentate κ 2 O , O' fashion. A phenylene-bridged proligand behaves differently, yielding a neutral methylaluminum complex bearing a κ 3 O , N , O' -coordinated FAlen ligand. From these complexes, methyl anion abstraction with B(C 6 F 5 ) 3 or a reaction with Schrock's alcohol leads to the corresponding aluminum cationic or alkoxy complexes in which a κ 4 O , N , N' , O' -coordination mode of the FAlen ligand is observed. X-ray diffraction studies of the proligands and of the complexes show that the amidine functions feature a trans configuration when the N -amidine atom is not coordinated to the metal and conversely a cis configuration when it is. Density functional theory calculations show that trans - cis isomerization of the amidine functions occurs upon coordination with the metal ion with very low energy barriers. They also confirm the intuition that the denticity of the FAlen ligands in the complexes is directly related to the electron richness of the metal ion. At last, FAlen Al complexes are used as initiators for the controlled ring-opening polymerization of rac -lactide to afford poly(lactic acid) with slight isotactic bias.

Aza-boron-dipyrromethenes (Aza-BODIPYs) are an increasingly studied class of fluorophores. They can be seen as an azadipyrromethene ("aza-DIPY") ligand rigidified by a metalloid, a boron atom. Based on this idea, a series of complexes of group 13 metals (aluminum and gallium) have been synthesized and characterized. The impact of the metal and of the nature of the substituents of aza-DIPY core were investigated. The photophysical and electrochemical properties were determined, and an X-ray structure of an azaGaDIPY was obtained. These data reveal that azaGaDIPY and azaAlDIPY exhibit significant red-shifted fluorescence compared to their analogue aza-BODIPY. Their emission can go up to 800 nm for the maximum emission length and up to NIR-II for the emission tail. This, associated with their electrochemical stability (no metal release whether oxidized or reduced) makes them a promising class of fluorophores for optical medical imaging. Moreover, X-ray structure and molecular modeling studies have shown that this redshift seems to be more due to the geometry around the boron/metal than to the nature of the metal.

Colloidal bismuth therapeutics have been used for hundreds of years, yet remain mysterious. Here we report an X-ray pair distribution function (PDF) study of the solvolysis of bismuth disalicylate, a model for the metallodrug bismuth subsalicylate (Pepto-Bismol). This reveals catalysis by traces of water, followed by multistep cluster growth. The ratio of the two major species, {Bi 9 O 7 } and {Bi 38 O 44 }, depends on exposure to air, time, and the solvent. The solution-phase cluster structures are of significantly higher symmetry in comparison to solid-state analogues, with reduced off-center Bi 3+ displacements. This explains why such "magic-size" clusters can be both stable enough to crystallize and sufficiently labile for further growth.

Two polymorphs, ( I ) and ( II ), of ( S )-{2-[(8 S ,9 S ,10 R ,11 S ,13 S ,14 S ,17 R )-11,17-dihy-droxy-10,13-dimethyl-3-oxo-2,6,7,8,9,11,12,14,15,16-deca-hydro-1 H -cyclo-penta-[ a ]phenanthren-17-yl]-2-oxoeth-yl} 2,2-di-methyl-propane-thio-ate, C 26 H 38 O 5 S, have been identified. They are ortho-rhom-bic, non-centrosymmetric ( P 2 1 2 1 2 1 ). The structures display layers of mol-ecules conected via O-H⋯O hydrogen bonds along the b- axis direction in polymorph ( I ) and along the c- axis direction in polymorph ( II ). The structure of ( II ) exhibits disorder of the main mol-ecule., (© Rousselin et al. 2021.)

The polymeric title compound, [Cu 2 Br 2 (C 4 H 8 S) 2 ] n , CP1 , represents an example of a two-dimensional coordination polymer resulting from reaction of CuBr with tetra-hydro-thio-phene (THT) in MeCN solution. The two-dimensional layers consist of two different types of rhomboid-shaped dinuclear Cu(μ 2 -Br) 2 Cu secondary building units (SBUs); one with a quite loose Cu⋯Cu separation of 3.3348 (10) Å and a second one with a much closer inter-metallic contact of 2.9044 (9) Å. These SBUs are inter-connected through bridging THT ligands, in which the S atom acts as a four-electron donor bridging each Cu(μ 2 -Br) 2 Cu unit in a μ 2 -bonding mode. In the crystal, the layers are linked by very weak C-H⋯·Br hydrogen bonds with H⋯Br distances of 2.95 Å, thus giving rise to a three-dimensional supra-molecular network., (© Knorr et al. 2021.)

A family of gold(i)-phosphonium-phosphine complexes was synthesized thanks to an efficient 5-step strategy, which involves a phospha-Fries rearrangement. It enables the facile variation of the phosphonium moiety. All the complexes along with a synthetic intermediate were fully characterized (a crystal structure was obtained for two of them). The antiproliferative properties of the six novel complexes were evaluated on three human cancer cell lines (A549, MDA-MB-231, and SW480) and compared to those of three benchmark anticancer drugs used in clinics (oxaliplatin, 5-fluorouracil, and paclitaxel) and to a phosphonium-free gold(i) complex [Au(PPh 3 )Br]. All the gold(i) complexes, containing a phosphonium, displayed strong anti-proliferative properties. They were more efficient than oxaliplatin and 5-fluorouracil, and one of the complexes was even more efficient than paclitaxel.

The reaction of [Re(CO)3(THF)(μ-Br)]2 or [Re(CO)5X] (X = Cl, Br, I) with the diaryl-2-azabutadienes [(RS)2C[double bond, length as m-dash]C(H)-N[double bond, length as m-dash]CAr2] containing two thioether arms at the 4,4-position forms the luminescent S,N-chelate complexes fac-[(OC)3ReX{(RS)2C[double bond, length as m-dash]C(H)-N[double bond, length as m-dash]CAr2}] (1a-h). The halide abstraction by silver triflate converts [(OC)3ReCl{(PhS)2C[double bond, length as m-dash]C(H)-N[double bond, length as m-dash]CPh2}] (1c) to [(OC)3Re(OS([double bond, length as m-dash]O)2CF3){(PhS)2C[double bond, length as m-dash]C(H)-N[double bond, length as m-dash]CPh2}] (1j) bearing a covalently bound triflate ligand. The cyclic voltammograms reveal reversible S^N ligand-centred reduction and irreversible oxidation waves for all complexes. The crystal structures of nine octahedral complexes have been determined along with that of (NaphtylS)2C[double bond, length as m-dash]C(H)-N[double bond, length as m-dash]CPh2 (L6). A rich system of weak non-covalent intermolecular secondary interactions through CHX(Cl, Br)Re, CHO, COπ(Ph), CHπCO, CHO and CHS contacts has been evidenced. The photophysical properties have been investigated by steady-state and time-resolved absorption (fs transient absorption, fs-TAS) and emission (ns-TCSPC and ps-Streak camera) spectroscopy in 2-MeTHF solution at 298 and 77 K. The emission bands are composed of either singlet (450 < λmax < 535 nm) and/or triplet emissions (at 77 K only, λmax < 640 nm, or appearing as a tail at λ > 600 nm), which decay in a multiexponential manner for the fluorescence (short ps (i.e.

We have recently patented an unprecedented stereospecific N → O phosphinyl migration process which transforms P-chirogenic aminophosphines into phosphinites. A fine design of aminophosphine phosphinite ligands (AMPP*) derived from ephedrine and bearing a P-chirogenic center either at the aminophosphine or phosphinite moiety was performed. The synthesis of AMPP* ligands with a P-chirogenic aminophosphine moiety was based on the well-established stereospecific reaction of oxazaphospholidine borane with organolithium reagents, followed by trapping with a chlorophosphine and borane decomplexation. Concurrently, the preparation of AMPP* ligands with a P-chirogenic phosphinite moiety was performed by N → O phosphinyl migration of aminophosphines borane by heating at 50 °C with DABCO and then reaction with chlorophosphines. AMPP* ligands were studied in palladium-catalyzed asymmetric allylic alkylations, leading to enantioselectivities from 91% ( R ) to 95% ee ( S ). X-ray crystallographic data for relevant Pd-AMPP* complexes and computer modeling explained the origin of the enantioselectivities based on MO interactions of most stable conformers with nucleophiles.

Twenty-nine fluorinated corroles were prepared, spectroscopically characterized, and studied for their antiviral activity against human cytomegalovirus infection. Six corroles were also fully characterized by X-ray crystallography giving insights on their geometrical features. The halogenated corroles reported herein exhibit significantly improved antiviral activity over their non-halogenated counterparts and over nitro-corrole analogs previously reported. Full activity of thirteen A 3 -corroles is achieved with four fluorine atoms present on the meso -phenyl ring reaching a selectivity index above 300. The maximum activity is achieved for A 2 B-corroles with selectivity indexes above 400. We thus demonstrate that the fluorocorrole is a highly potent platform to synthesize a new generation of anti hCMV molecules., (This journal is © The Royal Society of Chemistry 2020.)

A simple NIR-II emitting water-soluble system has been developed and applied in vitro and in vivo . In vitro , the fluorophore quickly accumulated in 2D and 3D cell cultures and rapidly reached the tumor in rodents, showing high NIR-II contrast for up to 1 week. This very efficient probe possesses all the qualities necessary for translation to the clinic as well as for the development of NIR-II emitting materials.

Diamondoids, sp 3 -hybridized nanometer-sized diamond-like hydrocarbons (nanodiamonds), difunctionalized with hydroxy and primary phosphine oxide groups, enable the assembly of the first sp 3 -C-based chemical sensors by vapor deposition. Both pristine nanodiamonds and palladium nanolayered composites can be used to detect toxic NO 2 and NH 3 gases. This carbon-based gas sensor technology allows reversible NO 2 detection down to 50 ppb and NH 3 detection at 25-100 ppm concentration with fast response and recovery processes at 100 °C. Reversible gas adsorption and detection is compatible with 50 % humidity conditions. Semiconducting p-type sensing properties are achieved from devices based on primary phosphine-diamantanol, in which high specific area (ca. 140 m 2  g -1 ) and channel nanoporosity derive from H-bonding., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Three cobalt dipyrrin-bisphenol (DPPCo) complexes with different meso-aryl groups (pentafluorophenyl, phenyl, and mesityl) were synthesized and characterized based on their electrochemistry and spectroscopic properties in nonaqueous media. Each DPPCo undergoes multiple oxidations and reductions with the potentials, reversibility, and number of processes depending on the specific solution conditions, the specific macrocyclic substituents, and the type and number of axially coordinated ligands on the central cobalt ion. Theoretical calculations of the compounds with different coordination numbers are given in the current study in order to elucidate the cobalt-ion oxidation state and the innocence or noninnocence of the macrocyclic ligand as a function of the changes in the solvent properties and degree of axial coordination. Electron paramagnetic resonance spectra of the compounds are obtained to experimentally assess the electron spin state. An X-ray structure of the six-coordinate complex is also presented. The investigated chemical properties of DPPCo compounds under different solution conditions are compared to those of cobalt corroles, where the macrocycle and metal ion also possess formal 3- and 3+ oxidation states in their air-stable forms.

The organic-inorganic title salt, (C 6 H 16 N) 2 [Sn(C 2 O 4 ) 2 Cl 2 ] or ( i Pr 2 NH 2 ) 2 [Sn(C 2 O 4 ) 2 Cl 2 ], was obtained by reacting bis-(diiso-propyl-ammonium) oxalate with tin(IV) chloride dihydrate in methanol. The Sn IV atom is coordinated by two chelating oxalate ligands and two chloride ions in cis positions, giving rise to an [Sn(C 2 O 4 ) 2 Cl 2 ] 2- anion (point group symmetry 2), with the Sn IV atom in a slightly distorted octa-hedral coordination. The cohesion of the crystal structure is ensured by the formation of N-H⋯O hydrogen bonding between ( i Pr 2 NH 2 ) + cations and [SnCl 2 (C 2 O 4 ) 2 ] 2- anions. This gives rise to an infinite chain structure extending parallel to [101]. The main inter-chain inter-actions are van der Waals forces. The electronic spectrum of the title compound displays only one high intensity band in the UV region assignable to ligand-metal ion charge-transfer (LMCT) transitions. An IR spectrum was also recorded and is discussed.

In the title compound, [Cu 2 (OH) 2 {C 12 H 7 N 2 (PO 3 C 2 H 5 )} 2 (H 2 O) 2 ]·7H 2 O, two Cu 2+ cations are bridged by two hydroxide groups, forming a centrosymmetric binuclear complex. Each Cu 2+ cation is further coordinated by the N atoms of a bidentate ethyl (1,10-phenanthrolin-3-yl)phospho-nate anion and a water mol-ecule in a square-pyramidal geometry. In the crystal, a network of O-H⋯O hydrogen bonds involving the P(O)(O - )(OEt) groups, bridging hydroxyl groups, coordinated and uncoordinated water mol-ecules generates a three-dimensional supra-molecular structure. The ethyl group exhibits disorder and was modelled over three sites with occupancies of 0.455, 0.384 and 0.161.

The organic-inorganic title salt, (C 6 H 16 N) 2 [MoO 4 ] or ( i Pr 2 NH 2 ) 2 [MoO 4 ], was obtained by reacting MoO 3 with diiso-propyl-amine in a 1:2 molar ratio in water. The molybdate anion is located on a twofold rotation axis and exhibits a slightly distorted tetra-hedral configuration. In the crystal structure, the diiso-propyl-ammmonium ( i Pr 2 NH 2 ) + cations and [MoO 4 ] 2- anions are linked to each other through N-H⋯O hydrogen bonds, generating rings with R 12 12 (36) motifs that give rise to the formation of a three-dimensional network. The structure was refined taking into account inversion twinning (ratio of ca 4:1 between the two domains).

A series consisting of a dyad, a triad and a tetrad containing either two, three and four BODIPY units, respectively, has been synthesized and fully characterized and compared to two mono-BODIPY analogs (used as references). The one- and two-photon photophysical properties have been measured and the X-ray structures of four of the BODIPY derivatives have been determined. In the 700-900 nm range, the two-photon absorption (TPA) cross sections range from 30 GM to 160 GM for these compounds., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A simple trifunctional BODIPY platform was designed. The high potential of this platform was validated via the elaboration of twelve optical theranostics. More specifically, we reported on the synthesis, the characterization, the photophysical properties, and the evaluation of the hydrophilicity properties of the different BODIPY derivatives, as well as a theoretical rationalization of the intriguing chemical behavior of some of them. The antiproliferative evaluation and confocal imaging of the different compounds in three human and murine cancer cell lines were performed and analysed, along with the measurement of gold(i) uptake in one cancer cell line via ICP-MS.

In the title compound, ( i Pr 2 NH 2 ) 2 [SnI 2 (C 2 O 4 ) 2 ], which was prepared by reacting ( i Pr 2 NH 2 + ) 2 ·C 2 O 4 2- with SnI 4 in a 2:1 molar ratio in a mixed ethanol-aceto-nitrile solvent, the Sn atom is coordinated by two chelating oxalate ions and two iodide ions, with the latter in a cis configuration. In the crystal, the cations are linked to the anions by N-H⋯O and bifurcated N-H⋯(O,O) hydrogen bonds, generating [10-1] chains.

Iron(III) and uranyl complexes of N-methylacetohydroxamic acid (NMAH) have been investigated by mass spectrometry, infrared multiphoton dissociation (IRMPD) spectroscopy, and density functional theory (DFT) calculations. A comparison between IRMPD and theoretical IR spectra enabled one to probe the structures for some selected complexes detected in the gas phase. The results show that coordination of Fe 3+ and UO 2 2+ by hydroxamic acid is of a very similar nature. Natural bond orbital analysis suggests that bonding in uranyl complexes possesses a slightly stronger ionic character than that in iron complexes. Collision-induced dissociation (CID), IRMPD, and 18 O-labeling experiments unambiguously revealed a rare example of the U═O bond activation concomitant with the elimination of a water molecule from the gaseous [UO 2 (NMA)(NMAH) 2 ] + complex. The U═O bond activation is observed only for complexes with one monodentate NMAH molecule forming a hydrogen bond toward one "yl" oxygen atom, as was found by DFT calculations. This reactivity might explain oxygen exchange observed for uranyl complexes.

A series of bis(pyridine)cobalt corroles with one or three nitrophenyl groups on the meso positions of the corrole macrocycle were synthesized and characterized as to their electrochemical and spectroscopic properties in dichloromethane, benzonitrile, and pyridine. The potentials for each electrode reaction were measured by cyclic voltammetry and the electron-transfer mechanisms evaluated by analysis of the electrochemical data combined with UV-visible spectra of the neutral, electroreduced, and electroxidized forms of the corroles. The proposed electronic configurations of the initial compounds and the prevailing redox reactions involving the electroactive central cobalt ion, the electroactive conjugated macrocycle, and the electroactive meso-nitrophenyl groups are all discussed in terms of solvent binding and the number of the nitrophenyl groups and other substituents on the meso-nitrophenyl rings of the compounds.

A series of open-chain pentapyrroles and sapphyrins with highly electron-withdrawing substituents (i.e., CN, CF 3 , or CO 2 Me) on the meso-phenyl rings was synthesized and characterized as to the spectral properties, protonation reactions, and electrochemistry in non-aqueous media. The investigated compounds are represented as (Ar) 4 PPyH 3 and (Ar) 4 SapH 3 where PPy and Sap correspond to the tri-anion of the open-chain pentapyrrole and sapphyrin, respectively, and Ar=p-CNPh, p-CF 3 Ph, or p-CO 2 MePh. UV/Vis and 1 H NMR spectroscopy as well as mass spectrometry data are given for the confirmation of the structures for the newly synthesized compounds. An X-ray structure for one of the pentapyrroles, that is, (p-CF 3 Ph) 4 PPyH 3 (2), is also presented. The protonation processes were examined by UV/Vis absorption spectroscopy during the titration of the compounds with trifluoroacetic acid (TFA) in CH 2 Cl 2 . Equilibrium constants for the protonation reactions were calculated by using both the Hill equation and the mole ratio method. The protonation-initiated conversion of pentapyrroles to sapphyrins upon oxidation was also investigated. Cyclic voltammetry was used to measure the redox potentials in CH 2 Cl 2 , PhCN, and/or pyridine (Py). Electrochemical properties, protonation constants, and chemical reactions of the six compounds in the two series were then analyzed as a function of the solvent properties and the type of the electron-withdrawing groups on the meso-phenyl rings., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The title compound, C12H10Br2N2O2, represents an example of a planar π-con-jugated 2-aza-butadiene mol-ecule, which is both an inter-esting starting material for further organic transformations and a potential ligand in organometallic coordination chemistry. Its metric mol-ecular parameters are typical for the family of 2-aza-buta-1,3-dienes not substituted at the (CH) 3-position. In the crystal, the almost planar (r.m.s. deviation = 0.0658 Å) aza-diene mol-ecules form one-dimensional double-wide ribbons through inter-molecular halogen bonds (C-Br⋯O and C-Br⋯Br-C), which then stack in a slipped manner through weak C-H⋯Br and π-π inter-actions to generate a three-dimensional network.

A new enantiodivergent synthesis of P-chirogenic 1,2-diphosphinobenzenes (DP*B) bearing the chirality on one or both phosphorus centers is reported using aryne chemistry. The principle is based on successive reactions of 1,2-dibromobenzene with sec-phosphide boranes, then DABCO to remove the borane, and finally with chlorophosphines or P(III)-chirogenic phosphinites. The efficiency of this synthesis was demonstrated by the stereoselective preparation of (S,S)-1,2-bis(o-anisylphenylphosphino)benzene. A comparison of DIPAMP and homochiral DP*B ligands in asymmetric Rh- or Pd-catalyzed reactions was reported.

The CuI- or Ag₂CO₃-catalyzed [3+2] cycloaddition of propargyl-substituted dihydroisoindolin-1-one (3) with arylnitrile oxides 1a-d (Ar = Ph, p-MeC₆H₄, p-MeOC₆H₄, p-ClC₆H₄) produces in good yields novel 3,5-disubstituted isoxazoles 4 of the ethyl-2-benzyl-3-oxo-1-((3-arylisoxazol-5yl)methyl)-2,3-dihydro-1H-isoindole-1-carboxylate type. With aryl azides 2a-d (Ar = Ph, p-MeC₆H₄, p-OMeC₆H₄, p-ClC₆H₄), a series of 1,4-disubstituted 1,2,3-triazoles 6 (ethyl-2-benzyl-3-oxo-1-((1-aryl-1H-1,2,3-triazol-4-yl)methyl)-2,3-dihydro-1H-isoindole-1-carboxylates) was obtained. The reactions proceed in a regioselective manner affording exclusively racemic adducts 4 and 6. Compared to the uncatalyzed cycloaddition, the yields are significantly improved in the presence of CuI as catalyst, without alteration of the selectivity. The regio- and stereochemistry of the cycloadducts has been corroborated by an X-ray diffraction study of 4a, and in the case of 6a by XH-correlation and HMBC spectra.

A series of ditopic macrocyclic receptors with variable cavity sizes, containing nitrogen or mixed (nitrogen-oxygen) donor sites and an externally directed 1,10-phenanthroline fragment, were prepared by means of a palladium-catalyzed amination reaction. A ditopic mixed NO-ligand (4 a) was coordinated to [Ru(bpy) 2 ] 2+ (bpy=2,2'-bipyridine) to prepare a luminescent and chromogenic complex, [Ru(bpy) 2 (4 a)][PF] 2 , which provided the selective dual-channel detection of Cu II ions., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In the title compound, [Fe(III)(C48H36N4O2)(H2O)2][K(C12H24O6)(H2O)2](SO3CF3)2·2C12H24O6, the Fe(III) atom is situated on an inversion centre and is octa-hedrally coordin-ated by four pyrrole N atoms of the deprotenated 5,10,15,20-tetra-kis-(4-meth-oxy-phen-yl)porphyrinate ligand and two water mol-ecules. The average equatorial Fe-N(pyrrole) bond length [2.043 (6) Å] is consistent with a high-spin (S = 5/2) iron(III) metalloporphyrin derivative. The K(+) cation, which also lies on an inversion centre, is chelated by the six O atoms of one 18-crown-6 mol-ecule and is additionally coordinated by two water mol-ecules in a distorted hexa-gonal-bipyramidal geometry. In the crystal, the cations, anions and one non-coordinating 18-crown-6 mol-ecule are linked by classical O-H⋯O hydrogen bonds and non-conventional C-H⋯O hydrogen bonds, leading to a one-dimensional supra-molecular architecture along [10-1]. The crystal packing is further stabilized by weak C-H⋯π inter-actions involving pyrrole and phenyl rings of the porphyrins, as well as weak C-H⋯F contacts involving the (SO3CF3)(-) counter-ion and the 18-crown-6 mol-ecules.

The thermodynamics and kinetics of the cis/trans isomerism of N-methylacetohydroxamic acid (NMAH) and its conjugated base (NMA(-)) have been reinvestigated in aqueous media by (1)H NMR spectroscopy. Hindered rotation around the central C-N bond due to electronic delocalization becomes slow enough on the NMR time scale to observe both rotamers in equilibrium in D2O at room temperature. By properly assigning the methyl group resonances, evidence for the prevalence of the E over the Z form is unambiguously provided [K300=[E]/[Z]=2.86(2) and 9.63(5) for NMAH and NMA(-), respectively], closing thereby a long-lasting dispute about the most stable conformer. To that end, calculations of the chemical shifts by density functional theory (DFT), which accurately reproduced the experimental data, turned out to be a much more reliable method than the direct computation of the relative energy for each conformer. The Z ⇌ E interconversion dynamics was probed at 300 K in D2O by 2D exchange-correlated spectroscopy (EXSY), affording the associated rate constants [kZE=9.0(2) s(-1) and kEZ=3.14(5) s(-1) for NMAH, kZE=0.96(3) s(-1) and kEZ=0.10(2) s(-1) for NMA(-)] and activation barriers at 300 K [ΔG(≠)ZE=68.0 kJ mol(-1) and ΔG(≠)EZ=70.6 kJ mol(-1) for NMAH, ΔG(≠)ZE=73.6 kJ mol(-1) and ΔG(≠)EZ=79.2 kJ mol(-1) for NMA(-)]. For the first time, mono- and bis-chelated uranium(VI) complexes of NMA(-) have been isolated. Crystals of [UO2(NMA)(NO3)(H2O)2] and [UO2(NMA)2(H2O)] have been characterized by X-ray diffractometry, infrared and Raman spectroscopies., (Copyright © 2015 Elsevier Inc. All rights reserved.)

A series of original spiropyrrolizidine derivatives has been prepared by a one-pot three-component [3 + 2] cycloaddition reaction of (E)-3-arylidene-1-phenyl-pyrrolidine-2,5-diones, l-proline, and the cyclic ketones 1H-indole-2,3-dione (isatin), indenoquinoxaline-11-one and acenaphthenequinone. We disclose an unprecedented isomerization of some spiroadducts leading to a new family of spirooxindolepyrrolizidines. Furthermore, these cycloadducts underwent retro-1,3-dipolar cycloaddition yielding unexpected regioisomers. Upon treatment of the dipolarophiles with in situ generated azomethine ylides from l-proline or acenaphthenequinone, formation of spiroadducts and unusual polycyclic fused piperazines through a stepwise [3 + 3] cycloaddition pathway is observed. The stereochemistry of these N-heterocycles has been confirmed by several X-ray diffraction studies. Some of these compounds exhibit extensive hydrogen bonding in the crystalline state. To enlighten the observed regio- and stereoselectivity of the [3 + 2] cycloaddition, calculations using the DFT approach at the B3LYP/6-31G(d,p) level were carried out. It was found that this reaction is under kinetic control.

The title compound, C11H11FO2, is a building block in the synthesis of the active pharmaceutical ingredient dl-nebivolol. The synthesis starting from the enanti-omerically pure (R)-6-fluoro-4-oxo-3,4-di-hydro-2H-chromene-2-carb-oxy-lic acid resulted in a mixture of two stereoisomers, namely (R)-6-fluoro-2-[(S)-oxiran-2-yl]chroman and (R)-6-fluoro-2-[(R)-oxiran-2-yl]chroman. The mixture was separated by column chromatography but only one stereoisomer crystallized. The X-ray structure analysis revealed that the solid consisted of the R,S isomer. A similar procedure was repeated for (S)-6-fluoro-4-oxo-3,4-di-hydro-2H-chromene-2-carb-oxy-lic acid and, in this case, the S,R isomer was produced as a crystalline solid. Thus, all four stereoisomers of the title epoxide were obtained and their absolute configuration was assigned. The crystal studied was refined as an inversion twin.

The 1D coordination polymer (CP) [(Me2S)3{Cu2(μ-I)2}]n (1) is formed when CuI reacts with SMe2 in n-heptane, whereas in acetonitrile (MeCN), the reaction forms exclusively the 2D CP [(Me2S)3{Cu4(μ-I)4}]n (2) containing "flower-basket" Cu4I4 units. The reaction product of CuI with MeSEt is also solvent-dependent, where the 1D polymer [(MeSEt)2{Cu4(μ3-I)2(μ2-I)2}(MeCN)2]n (3) containing "stepped-cubane" Cu4I4 units is isolated in MeCN. In contrast, the reaction in n-heptane affords the 1D CP [(MeSEt)3{Cu4(μ3-I)4}]n (4) containing "closed-cubane" Cu4I4 clusters. The reaction of MeSPr with CuI provides the structurally related 1D CP [(MeSPr)3{Cu4(μ3-I)4}]n (5), for which the X-ray structure has been determined at 115, 155, 195, 235, and 275 K, addressing the evolution of the metric parameters. Similarly to 4 and the previously reported CP [(Et2S)3{Cu4(μ3-I)4}]n (Inorg. Chem. 2010, 49, 5834), the 1D chain is built upon closed cubanes Cu4(μ3-I)4 as secondary building units (SBUs) interconnected via μ-MeSPr ligands. The 0D tetranuclear clusters [(L)4{Cu4(μ3-I)4}] [L = EtSPr (6), Pr2S (7)] respectively result from the reaction of CuI with EtSPr and n-Pr2S. With i-Pr2S, the octanuclear cluster [(i-Pr2S)6{Cu8(μ3-I)3}(μ4-I)2}] (8) is formed. An X-ray study has also been performed at five different temperatures for the 2D polymer [(Cu3Br3)(MeSEt)3]n (9) formed from the reaction between CuBr and MeSEt in heptane. The unprecedented framework of 9 consists of layers with alternating Cu(μ2-Br)2Cu rhomboids, which are connected through two μ-MeSEt ligands to tetranuclear open-cubane Cu4Br4 SBUs. MeSPr forms with CuBr in heptane the 1D CP [(Cu3Br3)(MeSPr)3]n (10), which is converted to a 2D metal-organic framework [(Cu5Br5)(μ2-MeSPr)3]n (11) incorporating pentanuclear [(Cu5(μ4-Br)(μ2-Br)] SBUs when recrystallized in MeCN. The thermal stability and photophysical properties of these materials are also reported.