(m‐CH3C6H4NH3)6P6O18

In hexakis(m‐toluidinium) cyclo­hexaphosphate, 6C₇H₁₀N⁺·­P₆O₁₈^6?, the atomic arrangement is typical of a layer structure. Layers including the centrosymmetric P₆O₁₈ ring anions develop around the (100) planes at x = . The hydrogen‐bond distribution is described.     

Totalsynthese von (+)-D-Homoöstron-3-methyläther

Total Synthesis of (+)-D-Homoestrone 3-methyl ether A novel total synthesis of (+)-D-homoestrone 3-methyl ether ( 21 ) is described starting from (S)-8a-methyl-3,4,8,8a-tetrahydro-2H, 7H-naphthalene-1,6-dione ( 1 ) as a chiral synthon for the rings C and D. The key step involves alkylation of the derived 3 with m-methoxyphenacyl bromide ( 4 ) as an AB-building block to give the dioxo-secosteroid 5 . Hydrogenation of 5 affords the trans-decalone 11 . As by-products the epimeric cis-decalones 12 and 13 were characterized. Cyclization of 11 leads under kinetic control predominantly to the Δ⁹⁽¹¹⁾-tetraene 14 . Catalytic hydrogenation of 14 and subsequent modification in ring D give the title compound 21 . It was found that 14 and also the derived Δ⁸-isomer 15a add hydrogen from the α-face of the molecule to an extent of about 80%. The 8α-D-homoestrone derivatives 20a and 23 as well as the 9β-isomers 19a and 22 were characterized.     

The Crystal Structure of ζ2‐Al3Cu4‐δ

The crystal structure of the ζ₂‐phase Al₃Cu_4‐δ was determined by means of X‐ray powder diffraction: a = 409.72(1) pm, b = 703.13(2) pm, c = 997.93(3) pm, space group Imm2, Pearson symbol oI24‐3.5, R_I = 0.0696. ζ₂‐Al₃Cu_4‐δ forms a distinctive a × √3a × 2c superstructure of a metal deficient Ni₂In‐type‐related structure. The phase is meta‐stable at ambient temperature. Between 400 °C and 450 °C it decomposes into ζ₁‐Al₃Cu₄ and η₂‐AlCu. Entropic contributions to the stability of ζ₂‐Al₃Cu_4‐δ are reflected in three statistically or partially occupied sites.     

Synthesis of 6aλ4-thia-1,6-diselena-3,4-diazapentalenes, 1,6,6aλ4-triselena-3,4-diazapentalenes, 6aλ4-thia-1,3,4,6-tetraazapentalenes,and 6aλ4-Selena-1,3,4,6-tetraazapentalenes from cyclic thioureas and selenoureas

Imidazolidine-2-thione (7a) and the corresponding 2-selone (7b), hexahydropyrimidine-2-thione (7c) and 2-selone (7d), and hexahydro-1H-1,3-diazepine-2-thione (7e) and 2-selone (7f) reacted with 2,4-dinitrobenzyl chloride to give the 2-(2,4-dinitrobenzylthio) and 2-(2,4-dinitrobenzylseleno) derivatives (8a)-(8f) of 4,5-dihydroimidazolium chloride, 1,4,5,6-tetrahydropyr-imidinium chloride, and 4,5,6,7-tetrahydro-1H-1,3-diazepinium chloride. Deprotonation of the chlorides (8a)-(8f) gave, respectively, 2-(2,4-dinitrobenzylthio)-and 2-(2,4-dinitrobenzylseleno)-4,5-dihydroimidazole (9a) and (9b), 2-(2,4-dinitrobenzylthio)- and 2-(2,4-dinitrobenzylseleno)-1,4,5,6-tetrahydropyrimidine (9c) and (9d), and 2-(2,4-dinitrobenzylthio)- and 2-(2,4-dinitrobenzylseleno)-4,5,6,7-tetrahydro-1H-1,3-diazepine (9e) and (9f). The bases (9a)-(9f) reacted with isoselenocyanates with elimination of 2,4-dinitrotoluene and concomitant addition of two molecules of the isoselenocyanate to give 1,6,6aλ⁴-triheterapentalenes of two structural types, depending on the size of the heteroring in the bases (9a)-(9f). The imidazoles (9a) and (9b) gave 6aλ⁴-thia-1,6-diselena-3,4-diazapentalenes (10a)-(10j) and 1,6,6aλ⁴-triselena-3,4-diazapentalenes (11a)-(11h), respectively. The sulfur-containing bases (9c) and (9e) gave 6aλ⁴-thia-1,3,4,6-tetraazapentalenes (12a)-(12j) and (14a)-(14d), respectively, and the selenium-containing bases (9d) and (9f) gave 6aλ⁴-selena-1,3,4,6-tetraazapentalenes (13a)-(13j) and (15a)-(15d). Heteroatom-heteroatom covalent bond energies have been estimated for representative members of the series (10)-(14) by using the Huggins equation and experimentally determined bond lengths. © 1997 John Wiley & Sons, Inc.     

Secoandrostansäuren als enantiomere prostaglandin-analoga—II : 6-pentyl-4-nor-3,5-seco-androstan-3-säuren

A synthesis of the enantiomeric tetrahydro-PGA₁ analogue 48 is described. In addition the homoacid 50, its pentanor analogue 39 and its epimer 51, the 6-deoxy compounds 13 and 16 as well as the lactones 14, 53, 56 and 68 were prepared as compounds closely related to 48. Simple androstane derivatives served as starting materials for the syntheses. Key intermediates were 4, 32 and 63.     

Über einige Eigenschaften von 6-Keto-δ7-Steroiden

Some aspects of the ORD.-, UV.-, and NMR.-spectra of 6-keto-δ⁷-steroids are discussed. It is shown that there exists a correlation between the configuration of rings A/B and the position of the maxima of the ORD. curves. On treatment with bases the 6-keto-δ⁷ group is unstable and undergoes deconjugation to δ⁸⁽¹⁴⁾-steroids.     

Ca4IrO6, Ca3MgIrO6 and Ca3ZnIrO6

Single crystals of tetracalcium iridium hexaoxide, Ca₄IrO₆, tricalcium magnesium iridium hexaoxide, Ca₃MgIrO₆, and tricalcium zinc iridium hexaoxide, Ca₃ZnIrO₆, were prepared via high-temperature flux growth and structurally characterized by single-crystal X-ray diffraction. The three compounds are isostructural and adopt the K₄CdCl₆ structure type, comprised of chains of alternating face-shared [CaO₆], [MgO₆] or [ZnO₆] trigonal prisms and [IrO₆] octahedra, surrounded by columns of Ca²⁺ ions.     

Cs4[La(NO3)6](NO3). HNO3: Das erste Salpetersäureaddukt eines ternären Alkali-Lanthanidnitrats

Cs₄[La(NO₃)₆](NO₃) · HNO₃: The First Nitric Acid Adduct of a Ternary Alkali Lanthanide Nitrate In the crystal structure of Cs₄[La(NO₃)₆](NO₃). HNO₃ (monoclinic, P2₁/c, Z = 2, a = 787.3(2); b = 1353.0(3); c = 1141.8(7) pm; β = 94,37(3)°) La³⁺ has a coordination number of twelve (six bidentate nitrate ligands). The structure may be viewed at as a layer structure: Layers of the composition [Cs(1)₄La₂(NO₃)₁₂]^2?, and [Cs(2)₄(NO₃)₂(HNO₃)₂]²⁺ are stacked alternatively in the [100] direction.     

Synthesis and Crystal Structure of [Nd(η6‐1, 3, 5‐C6H3Me3)‐(AlCl4)3](C6H6) and Structural Comparison of Ln(η6‐arene)‐(AlCl4)3

Reaction of Ndcl₃ with AlCl₃ and mesitylene in benzene gives complex [Nd(η⁶‐1, 3, 5‐C₆H₃Me₃)‐(AlCl₄)₃](C₆H₆) (1) which was characterized by elemental analysis, IR spectra, MS and X‐ray diffractions. The X‐ray determination indicates that 1 has a distorted pentagonal bipyramidal geometry and crystallizes in the monoclinic, space group P2₁/n with a = 0.9586(2), b = 1.1717(5), c = 2.8966(7) nm, β = 90.85 (2)°, V = 3.2529 (6) nm³,D_c= 1.573 g/cm³, Z = 4. A comparison of bond parameters for all the reported Ln (η⁶‐Ar) (AlCl₄)₃ complexes indicates that the bond distance of La? C is shortened with the increasing of methyl group on benzene and with the decreasing of radius of lanthanide ions.     

Über Glasbildung und Eigenschaften von Chalkogenidsystemen. XIII. Über die Verbindungen Na6Ge2S6 · 4 CH3OH und Na6Ge2Se6 · 4 CH3OH

Glass Formation and Properties of Chalcogenide Systems. XIII. On the Compounds Na₆Ge₂S₆ · 4 CH₃OH and Na₆Ge₂Se₆ · 4 CH₃OH The glasses Ge₂S₃ and Ge₂Se₃ are soluble in solutions of Na₂S or Na₂Se in CH₃OH forming Na₆Ge₂S₆ · 4 CH₃OH and Na₆Ge₂Se₆ · 4 CH₃OH. On heating the CH₃OH-free substances are formed. From the i.r. and Raman spectra can de seen that the structure of the ions Ge₂S, Ge₂Se, P₂S₆^4?, and of Si₂Cl₆ is of the same type. The formation of the compounds can be regarded as a chemical proof for the existence of [Ge₂S₆] and [Ge₂Se₆] units as structural groups in the glasses Ge₂S₃ and Ge₂Se₃.