Quasi-1D cations 1 infinity [Ni8Bi8S]n + of variable charge: infinite columns 1 infinity [Ni8Bi8S]2+ in the novel compound Ni8Bi8SI2

The new compound Ni(8)Bi(8)SI(2) has been synthesized and its crystal structure determined by X-ray crystallography. The structure contains one-dimensional (1D) cations (1)( infinity )[Ni(8)Bi(8)S](2+) separated by iodine anions. The geometry of the columns is similar to that of the recently reported (1)( infinity )[Ni(8)Bi(8)S](+), and the main difference between them is only their formal charge. Electronic structure calculations and physical properties measurements were performed to analyze the influence of the number of valence electrons on the bonding and properties of compounds containing these 1D cations. It was shown that the removal of one electron (i.e., (1)( infinity )[Ni(8)Bi(8)S](+) --> (1)( infinity )[Ni(8)Bi(8)S](2+)) mainly affects the Ni-S bonding within the cation and essentially has no influence on the intermetallic Ni-Bi bonding. It was found that Ni(8)Bi(8)SI(2) containing double-charged columns has conductivity properties more similar to a pure 1D metal than the congener Ni(8)Bi(8)SI containing mono-charged columns.     

Cr8S11Cl2 – das erste Chromthiochlorid

Cr₈S₁₁Cl₂ – the First Chromium Thiochloride Cr₈S₁₁Cl₂ was obtained by reaction of CrCl₃ with H₂S at 650 K. X-ray, magnetic and thermal properties have been investigated.     

Synthèse d'homologues de la (–)--(1R,2S)-norephedrine

Synthesis of (–)-(1R,2S)-Norephedrine Homologues The amino function of esters of some simple natural amino acids I is blocked in the form of a cyanoenamine by means of 2-oxocyclopentanecarbonitrile, so that the corresponding cyanoenamino esters II are obtained. The reaction of a disubstituted lithium amide with II leeds to the cyanoenamino-amides VI . The amide function present in VI is then transformed into an aromatic ketone by means of phenyllithium, to give the (benzoylalkyl)aminocyclopentenecarbonitriles VII . Reduction of Compounds VII with NaBH₄ in EtOH ?80° affects only the keto function and leads to the [(α-hydroxybenzyl)alkyl]amino-cyclopentenecarbonitriles VIII . The amino function is then deprotected by acid hydrolysis to give the amino-alcohols IX with yields close to 50%; in every amino-alcohol IX , the erythro isomer, homologous to natural (–)-(1R,2S)-norephedrine is the more abundant or the single product. All the polyfunctional compounds prepared conserve optical activity; it has been demonstrated that the amino-alcohols IX are pure enantiomers and that no racemisation lakes place at any step of their synthesis.     

New Mixed Ligand Organotellurium(IV) Compounds Containing Dithiocarbamates and the More Flexible Imidotetraphenyldithiodiphosphinates. The Crystal Structures of C8H8Te(S2CNEt2)[(SPPh2)2N] · H2O,C8H8Te(S2CNC5H10)[(SPPh2)2N], and C8H8Te(S2CNC4H8S)[(SPPh2)2N]

The synthesis of the following mixed ligand organotellurium(IV) compounds C₈H₈Te(S₂CNEt₂)[(SPPh₂)₂N] · H₂O ( 1 ), C₈H₈Te(S₂CNC₅H₁₀)[(SPPh₂)₂N] ( 2 ), C₈H₈Te(S₂CNC₄H₈O)[(SPPh₂)₂N] ( 3 ) and C₈H₈Te(S₂CNC₄H₈S)[(SPPh₂)₂N] ( 4 ) was achieved. They were characterized by IR, ¹H, ¹³C, ³¹P and ¹²⁵Te NMR, mass spectroscopy, and elemental analyses. The X‐ray crystal structures of 1 , 2 and 4 were determined. The both types of ligands display an asymmetrical chelating coordination mode on interaction with the tellurium atom. When these aniso‐bonded donor atoms are included in the coordination sphere, the tellurium atom exhibit an effective co‐ordination number of seven. The arrangement may be described as 1 : 2 : 2 : 2 coordination with a presumably stereoactive lone‐pair of electrons.     

A mixed‐valent niobium oxy­sulfide,La2Nb3S2O8

Dilanthanum triniobium di­sulfide octaoxide, La₂Nb₃S₂O₈, crystallizes in the orthorhombic space group Pnnm and is isostructural with the Ln₂Ta₃X₂O₈ (Ln = La, Ce, Pr and Nd, and X = S and Se) family of tantalum compounds. Nb⁴⁺ and Nb⁵⁺ ions co‐exist in the structure and occupy different crystallographic sites. While the Nb⁴⁺ ions are found in mixed oxy­gen and sulfur octahedra, the Nb⁵⁺ ions are found in oxy­gen‐only octahedra.     

Synthèse de la désamino1-Orn8-vasopressine,de la désamino1-Phe2-Orn8-vasopressine,de la désamino1-Ile3-Orn8-vasopressine (= désamino1-Orn8-oxytocine) et de la désamino1-Phe2-Ile3-Orn8-vasopressine (= désamino1 -Phe2-Orn8-oxytocine)

Four analogues of the vasopressins have been synthesised: Deamino¹-Orn⁸-vasopressin, Deamino¹-Phe²-Orn⁸-vasopressin, Deamino¹-Ile³-Orn⁸-vasopressin (= Deamino¹-Orn⁸-oxytocin) and Deamino¹-Phe²-Ile³-Orn⁸-vasopressin (= Deamino¹-Phe²-Orn⁸-oxytocin). The two former have been prepared by condensation of tripeptide azides with an hexapeptide. The two latter have been obtained from the hexapeptide by the recurring method, using active trichlorophenyl esters.     

Synthese und Röntgenstrukturanalyse des 8π-Elektronenringsystems S4N4O2Sn2(CH3)6 und des magnetische Verhalten von S4N4O2 und S8N8O4

Synthesis and X-Ray Structure Analysis of the 8π-Electron-Ring-System S₄N₄O₂Sn₂(CH₃)₆ and the Magnetic Properties of S₄N₄O₂ and S₈N₈O₄ S₄N₄O₂ reacts with N[Sn(CH₃)₃]₃ in a molar ratio of 1:1 to an eight-membered trimethyltin-substituted 8π-electron skeleton, S₄N₄O₂Sn₂(CH₃)₆. In contrast to known 6π-electronsystems this compound has tin atoms which are tetracoordinated. This was demonstrated on the basis of an x-ray analysis. S₄N₄O₂Sn₂(CH₃)₆ · 1/2 C₆H₆ crystallizes in the space group P2₁/c with a = 1396.0(4), b = 1190.3(4), c = 1256.7(3) pm, and β = 103.46(2)°. It was shown that the ability of coordination at the tin atom depends on the electron density. The magnetic properties of S₄N₄O₂ and S₈N₈O₄ were investigated by the Faraday method. The high diamagnetism in these ring compounds is caused by the π-electrons.     

(1S,2R,2′S)‐ and (1S,2S,2′S)‐1‐phenyl‐2‐phenyl­thio‐2‐(tetra­hydro­pyran‐2′‐yl­thio)­ethanol diastereoisomers at 193 K

In the synthesis of 1‐phenyl‐2‐phenyl­thio‐2‐(tetra­hydro­pyran‐2‐yl­thio)­ethanol, C₁₉H₂₂O₂S₂, four diastereoisomers are formed. Two non‐centrosymmetric enantiomeric forms which crystallize in space groups P2₁2₁2₁ and Pna2₁ are presented. The former has an intramolecular hydrogen bond between the hydroxyl group and the O atom of the tetra­hydro­pyran ring. In the latter isomer, the hydroxyl group forms an intermolecular hydrogen bond to the O atom of the tetra­hydro­pyran­yl group of a neighbouring mol­ecule, joining the mol­ecules into chains in the c‐axis direction; the O?O distances are 2.962 (4) and 2.764 (3) Å, respectively. The tetra­hydro­pyran rings are in chair conformations in both isomers and the S side chain has an equatorial orientation in the former, but an axial orientation in the latter mol­ecule.     

Über geordnete Perowskite mit Kationenfehlstellen. VIII. Strukturuntersuchungen an Ba2Ba7/8□1/8UO57/8□1/8

On ordered perovskites with cationic vacancies. VIII. Structure investigations on Ba₂Ba_7/8□_1/8UO_57/8□_1/8 The reddish brown Ba₂Ba_7/8□_1/8UO_57/8□_1/8 belongs to the group of oxygen perovskites with an ordered distribution of cationic vacancies. It crystallized tetragonally (a = 12.62₄ Å; c = 17.53₄ Å) with 16 formula units in the unit cell: Ba₃₂Ba₁₄□₂U₁₆O₉₄□₂. For the space group I4/mmm intensity calculations on powder data gave a refined, intensity related R′ value of 13.4%. The octahedrally coordinated barium an uranium atoms are 1:1 ordered; both cationic vacancies are located in the barium sublattice and form a body centered arrangement. For the 94 oxygen atoms and the two oxygen vacancies a statistical distribution was chosen. In the lattice all cations neighbouring the cationic vacancies are dislocated: The corresponding barium atoms in the close packed sheets move by ～0.55 Å in direction of the holes, on the contary the uranium atoms concerned are shifted away by ～0.17 Å and ～0.26 Å respectively.     

Heterotricyclodecane XX (+)-(1S, 3S, 6S, 8S)- und (−)-(1R, 3R, 6R, 8R)-2, 7-Dioxa-twista-4,9-dien

(+)-(1S, 3S, 6S, 8S)- and (?)-(1R, 3R, 6R, 8R)-2,7-dioxa-twista-4,9-diene. A synthesis and the determination of the sense of chirality of (+)-(1S, 3S, 6S, 8S)- and (?)-(1R, 3R, 6R, 8R)-2,7-dioxa-twista-4,9-diene ((+)- 5 and (?)- 5 , respectively) is described.