Über RhSCl ein hexamerer,molekularer Rhodium(III)‐Komplex mit SCl2‐Liganden

About RhSCl₅ — a Hexameric, Molecular Rhodium(III) Complex with SCl₂ Ligands Needle‐shaped red crystals of RhSCl₅ were obtained by reaction of Rh metall or RhI₃ with SCl₂ in a closed silica ampoule. In the monoclinic crystal structure the Rh atoms are octahedrally coordinated by 5 Cl atoms and a SCl₂ ligand. In each case six RhCl₅(SCl₂) groups are connected with each other by two common edges of Cl atoms to form hexameric molecules [RhCl₃(SCl₂)]₆. In the pseudohexagonal unit cell (monoclinic, space group C2/c, a = 26.215(5) Å, b = 6.7750(10) Å, c = 26.868(5) Å, β = 119.06(3)°, Z = 4) the molecules are stacked in columns and form a hexagonal rod package.     

Synthesen und Kristallstrukturen neuer Bromoferrate(III), Chloro‐ und Aquachloroferrate(III) mit tetraedrischer und oktaedrischer Eisenkoordination,darunter zwei Neutralkomplexe von Eisen(II) und ‐(III)

Halogeno Metallates of Transition Elements with Cations of Nitrogen‐containing Heterocyclic Bases. VIII Syntheses and Crystal Structures of Novel Bromoferrates(III), Chloro‐, and Aquachloroferrates(III) with Tetrahedral and Octahedral Iron Coordination, among them two Neutral Complexes of Iron(II) and (III) (dmpipzH₂)[Fe^IIIBr₄]₂ ( 1 ), (trienH₂)[Fe^IIIBr₄]Br ( 2 ), (dmpipzH₂)[Fe^IIICl₄]Cl ( 3 ), (dmpipzH₂)₂[Fe^III(H₂O)₂Cl₄][Fe^IIICl₄]Cl₂ ( 4 ), and (trienH₂)[Fe^III(H₂O)₃Cl₃]Cl₂ ( 5 ) crystallize from aqueous mineralic acid solutions of iron(II) halide and the organic bases (1,4‐dimethylpiperazine or triethylenediammine) in the presence of atmospheric oxygen whereas (dmpipzH₂)[FeCl₄(H₂O)₆]Cl₂ ( 6 ) was obtained under the exclusion of air. 1 , 2 , and 3 contain the known tetrahedral halogeno complexes, 4 contains a novel octahedral iron(III) complex, and in 6 a neutral binuclear iron(II) complex has been found which has not been described before. The crystal structures and the hydrogen bridging systems of the complexes are described.     

Phenyliodine(III) Bis(Trifluoroacetate) Mediated Synthesis of 2‐Aryl‐1,2‐Benzisothiazol‐3(2H)‐Ones in Ionic Liquid

Treatment of N‐aryl‐2‐(benzylthio)benzamides with phenyliodine(III) bis(trifluoroacetate) containing trifluoroacetic acid resulted in an interrupted Pummerer‐type reaction in ionic liquid 1‐n‐butyl‐3‐methylimidazolium hexafluorophosphate, [bmim][PF₆] to give 2‐aryl‐1,2‐benzisothiazol‐3(2H)‐ones rather than the normal Pummerer‐type products.     

Construction of a Highly Selective and Sensitive La(III) Sensor Based on N‐(2‐Pyridyl)‐N′‐(4‐methoxyphenyl)‐thiourea for Nano Level Monitoring of La(III) Ions

N‐(2‐Pyridyl)‐N′‐(4‐methoxyphenyl)‐thiourea (PMPT) was found to be a suitable neutral ion carrier for the construction of a highly selective and sensitive La(III) membrane sensor. Poly(vinyl chloride) (PVC) based membranes of PMPT with potassium tetrakis (p‐chlorophenyl) borate (KTpClPB) as an anionic excluder and oleic acid (OA), dibutyl phthalate (DBP), benzyl acetate (BA) and o‐nitrophenyloctyl ether (NPOE) as plasticizing solvent mediators were constructed and investigated as La(III) membrane sensors. A membrane composed of PMPT‐PVC‐KTpClPB‐BA with the ratio 8.0 : 35.0 : 3.0 : 54.0 works well over a very wide concentration range (4.0×10^?8 to 1.0×10^?1 M) with a Nernstian slope of 19.6±0.2 mV per decade of activity between pH values of 4.0 and 9.0. The detection limit of the sensor was calculated to be 2.0×10^?8 M (ca. 3.0 ppb). The sensor displays very good discrimination toward La(III) ions with regard to most common metal ions and lanthanide ions. The proposed sensor shows a short response time for whole concentration range (ca. 12 s). For evaluation of the analytical applicability of the La(III) sensor, it was successfully used as an indicator electrode for the titration of La(III) ions with EDTA. It was also applied to the determination of fluoride content of two mouth wash preparation samples and monitoring of La(III) ions in some binary and ternary mixtures.