ABSTRACT The reaction between the organopnicogen(III) chlorides R2MCl and RMCl2 [M = Sb, Bi; R = ... more ABSTRACT The reaction between the organopnicogen(III) chlorides R2MCl and RMCl2 [M = Sb, Bi; R = 2-(Me2NCH2)C6H4] and alkali metal pseudohalides in a 1:1 and a 1:2 molar ratio, respectively, resulted in the formation of hypervalent species of type R2MX (M = Sb, X = NCO (1), NCS (2) and SeCN (3), M = Bi, X = NCO (4) and SeCN (5), and RMX2 (M = Sb, X = NCO (6) and NCS (7), M = Bi, X = NCO (8), NCS (9) and SeCN (10). The new species were characterized by multinuclear NMR (H-1, C-13, Se-77 where appropriate), IR spectroscopy and mass spectrometry. The molecular structures of compounds 2-5 and 7 were determined by single-crystal X-ray diffraction. In all five compounds the nitrogen atoms in the pendant arms are involved in intramolecular coordination to metal, thus resulting in a distorted square pyramidal coordination geometry (12-M-5 hypervalent species) in case of 2-5 and a distorted trigonal pyramidal coordination geometry in case of 7 (10-Sb-4 hypervalent species). The intramolecular N -> M coordination determines a chiral pattern of the investigated compounds. Bi center dot center dot center dot Ph-centroid intermolecular interactions led to dimers in case of compound 4. In all species weak CH center dot center dot center dot Ph-centroid intermolecular contacts led to polymeric associations, e. g. polymeric chains in case of compounds 2, 3, 5 and 7 and a 2D layer structure built by chains of dimers in case of compound 4. DFT calculations and FTIR data allowed us to assign the coordination pattern of the pseudohalide ligand in the other species.
Intramolecular Bi⋯π arene London dispersion interactions in (biphenyl)3−xBiXx amount to ca. 20 kJ... more Intramolecular Bi⋯π arene London dispersion interactions in (biphenyl)3−xBiXx amount to ca. 20 kJ mol−1 with distances of 3.8–4.0 Å.
Environmental Engineering and Management Journal, 2009
A simple method to synthesize copper, nickel and Cu-Ni nanotubes in alumina membrane by direct el... more A simple method to synthesize copper, nickel and Cu-Ni nanotubes in alumina membrane by direct electrochemical deposition technique is presented. This work is divided into three main parts: elaboration of the nanostructured metals supported on Cu and Ni electroconductive support; SEM-EDX characterization of nanodeposits; electrochemical characterization of the nanostructured electrodes; Cu and Cu-Ni nanostructures were obtained by deposition through an alumina membrane (AAO) that is later dissolved. The diameter of the nanorods deposited on Cu foil is about 40-150 nanometres, which is in good agreement with the AAO membrane pore size used in the electrolysis process. The nanorods were found to be vertically aligned; their collapsing was observed with the height deposited, at high current densities. These nanostructure electrodes exhibit a high electrocatalytic activity both for oxygen reduction and carbon dioxide electroreduction to formic acid. Faradic efficiency up to 50% was obtained on (Ni-Cu) nano
NATO Science for Peace and Security Series C: Environmental Security, 2009
Abstract. Metal nanorod arrays and nanotubes are expected to exhibit unusual and interesting prop... more Abstract. Metal nanorod arrays and nanotubes are expected to exhibit unusual and interesting properties for possible application in electrocatalysis and fuel cell. This work is divided into four main parts: Elaboration of the template nanostructure metals (Cu and Cu-Ni) Structural ...
New diorganopnicogen(III) compounds of type [CH 3 OCH 2 CH 2 N(CH 2 C 6 H 4) 2 ]ML (M ¼ Sb, L ¼ O... more New diorganopnicogen(III) compounds of type [CH 3 OCH 2 CH 2 N(CH 2 C 6 H 4) 2 ]ML (M ¼ Sb, L ¼ ONO 2 (3), OSO 2 CF 3 (4); M ¼ Bi, L ¼ ONO 2 (5), OSO 2 CF 3 (6), OSO 2 C 6 H 4 (CHCH 2)-4 (7) based on a heterocyclic butterfly-like tetrahydro-dibenzo[c,f][1,5]azastibocine/azabismocine skeleton were prepared by ligand exchange reactions between [CH 3 OCH 2 CH 2 N(CH 2 C 6 H 4) 2 ]MX (M ¼ Sb, X ¼ Cl (1); M ¼ Bi, X ¼ Br (2) and the appropriate silver salt. The new compounds 1 and 3e7 were structurally characterized by NMR and IR spectroscopy. For compounds 5, 7‧CHCl 3 and the hydrolysis product [{CH 3 OCH 2 CH 2 N(CH 2 C 6 H 4) 2 } BiOH 2 ][CF 3 SO 3 ] (6h) the crystal and molecular structures were determined by single-crystal X-ray diffraction. Strong transannular N/Bi interactions accompanied by strong MeO/Bi intramolecular interactions result in hypercoordinated species: 14-Bi-6 in 5, with a unisobidentate ONO 2 ligand, and 12-Bi-5 in the cation of 6h and in 7‧CHCl 3 , with a monodentate OSO 2 C 6 H 4 (CHCH 2)-4 ligand. The molecules are associated in dimeric units by Bi/p arene interactions (approx. 3.50 Å). Weak H/O (in 5), H/p arene (in 7‧CHCl 3), H/p arene, H/O and H/F (in 6h) intermolecular interactions contribute to supramolecular networks in all three compounds.
Dalton transactions (Cambridge, England : 2003), Jan 7, 2017
New diorganobismuth(iii) bromides of type [RN(CH2C6H4)2]BiBr [R = C6H5CH2 (1), C6H5CH2CH2 (2), an... more New diorganobismuth(iii) bromides of type [RN(CH2C6H4)2]BiBr [R = C6H5CH2 (1), C6H5CH2CH2 (2), and CH3OCH2CH2 (3)], based on the heterocyclic butterfly-like tetrahydro-dibenzo[c,f][1,5]azabismocine framework, were prepared starting from the corresponding RN(CH2C6H4Br-2)2 in a succession of reactions including ortho-lithiation and treatment of the dilithio derivative with BiBr3 in a 1 : 1 molar ratio. Further exchange reactions between bromides and appropriate metal halides or ammonium fluoride resulted in the formation of [RN(CH2C6H4)2]BiX [X = Cl and I for R = C6H5CH2 (4 and 5) and C6H5CH2CH2 (6 and 7) and X = F (8), Cl (9), and I (10) for R = CH3OCH2CH2]. All ten compounds were structurally characterized in solution by NMR and in the solid state by single-crystal X-ray diffraction. Strong transannular N→Bi interactions were observed in all the investigated diorganobismuth(iii) halides, thus giving rise to hypervalent 10-Bi-4 species in 1, 2, 4-7 and 12-Bi-5 species in 3, 8-10, whe...
Abstract Diorganodichalcogenides of type [2-(C6H5O)C6H4]2E2 [E S (1), Se (2), Te (3)] were prepar... more Abstract Diorganodichalcogenides of type [2-(C6H5O)C6H4]2E2 [E S (1), Se (2), Te (3)] were prepared and structurally characterized by multinuclear NMR (1H, 13C, 77Se or 125Te, as appropriate) and ESI+ mass spectrometry. The oxidation reaction of the diorganodichalcogenides 2 and 3 with SO2Cl2 under anhydrous conditions led to the phenoxaselenine 10,10-dichloride (5) and to the organotellurium trichloride, [2-(C6H5O)C6H4]TeCl3 (4), respectively. Further hydrolysis with a KOH solution led to a mixture of phenoxachalcogenine 10-oxide [chalcogen = Se (7), Te (8)] and phenoxachalcogenine [chalcogen = Se (9), Te (10)] in each case. The crystal and molecular structures of compounds 2–5 and 7 were determined by single-crystal X-ray diffraction.
ABSTRACT The reaction between the organopnicogen(III) chlorides R2MCl and RMCl2 [M = Sb, Bi; R = ... more ABSTRACT The reaction between the organopnicogen(III) chlorides R2MCl and RMCl2 [M = Sb, Bi; R = 2-(Me2NCH2)C6H4] and alkali metal pseudohalides in a 1:1 and a 1:2 molar ratio, respectively, resulted in the formation of hypervalent species of type R2MX (M = Sb, X = NCO (1), NCS (2) and SeCN (3), M = Bi, X = NCO (4) and SeCN (5), and RMX2 (M = Sb, X = NCO (6) and NCS (7), M = Bi, X = NCO (8), NCS (9) and SeCN (10). The new species were characterized by multinuclear NMR (H-1, C-13, Se-77 where appropriate), IR spectroscopy and mass spectrometry. The molecular structures of compounds 2-5 and 7 were determined by single-crystal X-ray diffraction. In all five compounds the nitrogen atoms in the pendant arms are involved in intramolecular coordination to metal, thus resulting in a distorted square pyramidal coordination geometry (12-M-5 hypervalent species) in case of 2-5 and a distorted trigonal pyramidal coordination geometry in case of 7 (10-Sb-4 hypervalent species). The intramolecular N -> M coordination determines a chiral pattern of the investigated compounds. Bi center dot center dot center dot Ph-centroid intermolecular interactions led to dimers in case of compound 4. In all species weak CH center dot center dot center dot Ph-centroid intermolecular contacts led to polymeric associations, e. g. polymeric chains in case of compounds 2, 3, 5 and 7 and a 2D layer structure built by chains of dimers in case of compound 4. DFT calculations and FTIR data allowed us to assign the coordination pattern of the pseudohalide ligand in the other species.
Intramolecular Bi⋯π arene London dispersion interactions in (biphenyl)3−xBiXx amount to ca. 20 kJ... more Intramolecular Bi⋯π arene London dispersion interactions in (biphenyl)3−xBiXx amount to ca. 20 kJ mol−1 with distances of 3.8–4.0 Å.
Environmental Engineering and Management Journal, 2009
A simple method to synthesize copper, nickel and Cu-Ni nanotubes in alumina membrane by direct el... more A simple method to synthesize copper, nickel and Cu-Ni nanotubes in alumina membrane by direct electrochemical deposition technique is presented. This work is divided into three main parts: elaboration of the nanostructured metals supported on Cu and Ni electroconductive support; SEM-EDX characterization of nanodeposits; electrochemical characterization of the nanostructured electrodes; Cu and Cu-Ni nanostructures were obtained by deposition through an alumina membrane (AAO) that is later dissolved. The diameter of the nanorods deposited on Cu foil is about 40-150 nanometres, which is in good agreement with the AAO membrane pore size used in the electrolysis process. The nanorods were found to be vertically aligned; their collapsing was observed with the height deposited, at high current densities. These nanostructure electrodes exhibit a high electrocatalytic activity both for oxygen reduction and carbon dioxide electroreduction to formic acid. Faradic efficiency up to 50% was obtained on (Ni-Cu) nano
NATO Science for Peace and Security Series C: Environmental Security, 2009
Abstract. Metal nanorod arrays and nanotubes are expected to exhibit unusual and interesting prop... more Abstract. Metal nanorod arrays and nanotubes are expected to exhibit unusual and interesting properties for possible application in electrocatalysis and fuel cell. This work is divided into four main parts: Elaboration of the template nanostructure metals (Cu and Cu-Ni) Structural ...
New diorganopnicogen(III) compounds of type [CH 3 OCH 2 CH 2 N(CH 2 C 6 H 4) 2 ]ML (M ¼ Sb, L ¼ O... more New diorganopnicogen(III) compounds of type [CH 3 OCH 2 CH 2 N(CH 2 C 6 H 4) 2 ]ML (M ¼ Sb, L ¼ ONO 2 (3), OSO 2 CF 3 (4); M ¼ Bi, L ¼ ONO 2 (5), OSO 2 CF 3 (6), OSO 2 C 6 H 4 (CHCH 2)-4 (7) based on a heterocyclic butterfly-like tetrahydro-dibenzo[c,f][1,5]azastibocine/azabismocine skeleton were prepared by ligand exchange reactions between [CH 3 OCH 2 CH 2 N(CH 2 C 6 H 4) 2 ]MX (M ¼ Sb, X ¼ Cl (1); M ¼ Bi, X ¼ Br (2) and the appropriate silver salt. The new compounds 1 and 3e7 were structurally characterized by NMR and IR spectroscopy. For compounds 5, 7‧CHCl 3 and the hydrolysis product [{CH 3 OCH 2 CH 2 N(CH 2 C 6 H 4) 2 } BiOH 2 ][CF 3 SO 3 ] (6h) the crystal and molecular structures were determined by single-crystal X-ray diffraction. Strong transannular N/Bi interactions accompanied by strong MeO/Bi intramolecular interactions result in hypercoordinated species: 14-Bi-6 in 5, with a unisobidentate ONO 2 ligand, and 12-Bi-5 in the cation of 6h and in 7‧CHCl 3 , with a monodentate OSO 2 C 6 H 4 (CHCH 2)-4 ligand. The molecules are associated in dimeric units by Bi/p arene interactions (approx. 3.50 Å). Weak H/O (in 5), H/p arene (in 7‧CHCl 3), H/p arene, H/O and H/F (in 6h) intermolecular interactions contribute to supramolecular networks in all three compounds.
Dalton transactions (Cambridge, England : 2003), Jan 7, 2017
New diorganobismuth(iii) bromides of type [RN(CH2C6H4)2]BiBr [R = C6H5CH2 (1), C6H5CH2CH2 (2), an... more New diorganobismuth(iii) bromides of type [RN(CH2C6H4)2]BiBr [R = C6H5CH2 (1), C6H5CH2CH2 (2), and CH3OCH2CH2 (3)], based on the heterocyclic butterfly-like tetrahydro-dibenzo[c,f][1,5]azabismocine framework, were prepared starting from the corresponding RN(CH2C6H4Br-2)2 in a succession of reactions including ortho-lithiation and treatment of the dilithio derivative with BiBr3 in a 1 : 1 molar ratio. Further exchange reactions between bromides and appropriate metal halides or ammonium fluoride resulted in the formation of [RN(CH2C6H4)2]BiX [X = Cl and I for R = C6H5CH2 (4 and 5) and C6H5CH2CH2 (6 and 7) and X = F (8), Cl (9), and I (10) for R = CH3OCH2CH2]. All ten compounds were structurally characterized in solution by NMR and in the solid state by single-crystal X-ray diffraction. Strong transannular N→Bi interactions were observed in all the investigated diorganobismuth(iii) halides, thus giving rise to hypervalent 10-Bi-4 species in 1, 2, 4-7 and 12-Bi-5 species in 3, 8-10, whe...
Abstract Diorganodichalcogenides of type [2-(C6H5O)C6H4]2E2 [E S (1), Se (2), Te (3)] were prepar... more Abstract Diorganodichalcogenides of type [2-(C6H5O)C6H4]2E2 [E S (1), Se (2), Te (3)] were prepared and structurally characterized by multinuclear NMR (1H, 13C, 77Se or 125Te, as appropriate) and ESI+ mass spectrometry. The oxidation reaction of the diorganodichalcogenides 2 and 3 with SO2Cl2 under anhydrous conditions led to the phenoxaselenine 10,10-dichloride (5) and to the organotellurium trichloride, [2-(C6H5O)C6H4]TeCl3 (4), respectively. Further hydrolysis with a KOH solution led to a mixture of phenoxachalcogenine 10-oxide [chalcogen = Se (7), Te (8)] and phenoxachalcogenine [chalcogen = Se (9), Te (10)] in each case. The crystal and molecular structures of compounds 2–5 and 7 were determined by single-crystal X-ray diffraction.
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