Synthese von 5-Methyl-3-oxa-A-nor-5β-cholestan und 3-Oxa-Δ4-cholesten-2-on

2, 3-seco-Δ⁴-Cholestene-2, 3-dicarboxylic acid ( 5 ) was prepared in 30% yield from 2-hydroxymethylene-Δ⁴-cholestene-3-one ( 1 ) by ozonolysis under special conditions. Pyrolysis of the pure di-acid 5 gave A-nor-Δ³⁽⁵⁾-cholestene-2-one ( 6 ), the anhydride 2 and 5-methyl-3-oxa-A-nor-5β-cholestane-2-one ( 8 ). Pyrolysis of amorphous acidic material obtained by the ozonolysis of 1 yielded the enol-lactones 7 and 9 as additional products. LiA1H₄-reduction of the γ-lactone 8 gave the diol 10 , which was transformed into 5-methyl-3-oxa-A-nor-5β-cholestane ( 13 ) by treatment with tosyl chloride in pyridine.     

Die Reaktion von λ5-Diphospheten mit COS und CO2 Dihydro-λ5-Phosphete

Reactions of λ⁵-Diphosphetes with COS and CO₂. Dihydro-λ⁵-Phosphetes 1,1,3,3-Tetrakis(dimethylamino)-1λ⁵,3λ⁵-diphosphete, 1 , reacts with COS to yield the (3-oxo-3,4-dihydro-1λ⁵-phosphete-2-yl)-phosphonothioic bis(dimethylamide) 7 . Reaction of dimethyl substituted 1 , i.e. 1,1,3,3-tetrakis(dimethylamino)-2,4-dimethyl-1λ⁵,3λ⁵-diphosphete 4 , with COS and CO₂ results in (3-oxo-2,3-dihydro-1λ⁵-phosphete-2-yl)-phosphonothioic bis(dimethylamide) 9 , and (3-oxo-2,3-dihydro-1λ⁵-phosphete-2-yl)-phosphonic bis(dimethylamide) 10 , respectively. Reaction mechanisms are suggested. 7, 9 and 10 are characterized by their properties, and their nmr, mass-, and ir-spectra. The results of X-ray structural analyses of 9 and 10 are reported and discussed.     

Steroide und Sexualhormone. 248. Mitteilung. Die Partialsynthese von 5α-Dihydrohirundigenin und von 5α-dihydroanhydrohirundigenin

A partial synthesis of dihydroanhydrohirundigenin ( 4 ), a hydrogenation product of naturally occurring anhydrohirundigenin ( 2 ) is described. Furthermore 4 is transformed into the formal dihydroderivative 14 of hirundigenin ( 1 ).     

Synthese von Fluoro-λ5-monophosphazenen und Fluoro-1, 3-diaza-2λ5, 4λ5-diphosphetidinen mittels der Staudinger-Reaktion

Synthesis of Fluoro-λ⁵-monophosphazenes and Fluoro-1,3-diaza-2λ⁵,4λ⁵-diphosphetidines by Means of the Staudinger Reaction 35 Tetrafluoro- and 2 difluorodiaza-diphosphetidines as well as 4 difluoro- and 30 monofluoro-λ⁵-monophosphazenes were prepared by the Staudinger reaction between tervalent phosphorus fluorides, R_nPF_3?n (n = 1, 2; R = R₂N, (CH₂)₅N, O(CH₂)₄N, RO, (CH₂O)₂, alkyl, aryl) and phenylazides, X? C₆H₄N₃ (X = H, 4-CH₃, 4-Cl, 4-Br, 4-NO₂, 3-NO₂). PF₃ does not react with phenylazide The influence of substituents on the structure of the reaction products is discussed. Kinetic measurements allowed to determine the constants λ^P_I of the substituents (CH₂)₅N, O(CH₂)₄N and R(C₆H₅)N (R = CH₃, C₂H₅, n-C₄H₉).     

Darstellung von Bis‐(2‐chlorethyl)amino‐substituierten Diazaphosphorinonen. Reversible oxidative Addition von Hexafluoraceton an σ3λ3‐Phosphor‐Verbindungen. Synthese von σ5λ5‐Spirophosphoranen und deren Zersetzung

Synthesis of Bis‐(2‐chloroethyl)amino‐substituted Diazaphosphorinones. Reversible Oxidative Addition of Hexafluoroacetone to σ³λ³‐Phosphorus Compounds. Synthesis of σ⁵λ⁵‐Spirophosphoranes and their Decomposition The reaction of 1‐methyl‐pyrido[3,2‐e]‐3,1‐oxazin‐2,4‐dione ( 1 ) with benzylamines led to the aminonicotinic acid amides 2 – 4 . Their reaction with phosphorus trichloride furnished the P‐chloro‐pyridodiazaphosphorinones 5 – 7 , which, upon reaction with bis‐(2‐chloroethyl) ammonium chloride/triethylamine, were converted into the P‐bis‐(2‐chloroethyl)amino‐substituted pyridodiazaphosphorinones 8 – 10 . The P‐chloro‐benzodiazaphosphorinone 11 was allowed to react with 2‐chloroethylammonium chloride/triethylamine to form the 2‐chloroethylamino‐substituted derivative 12 . The σ³‐diazaphosphorinones 8 , 9 , 12 and 13 were oxidized with the urea‐hydrogen peroxide‐(1 : 1)‐adduct to the corresponding phosphoryl derivatives 14 – 17 . The oxidative addition of hexafluoroacetone (HFA) to the σ³‐diazaphosphorinone 18 led, with abstraction of methyl chloride, to the tricyclic phosphorane 19 b . The spirophosphoranes 21 – 23 were formed by reaction of compounds 8 , 9 and 13 with HFA. NMR‐studies were made on the decomposition of the bicyclic phosphoranes 20 a , 22 and 23 . The oxidative addition of HFA to diazaphosphorinones was found to be reversible. Single crystal X‐ray determinations were conducted on compounds 17 and 19 b . They confirm the expected connectivity. Compound 17 was found to exhibit short C–H‥ O‐hydrogen bonds (H…O 234 pm). Compound 19 crystallises as two independent molecules which differ, e. g., in the orientation of the chloroethyl groups.     

Gas-Chromatographie und Massenspektrometrie der Trimethylsilyl-enoläther von 5α- und 5β-Cholestan-3-on

Trimethylsilyl-enolethers of 5α- and 5β-cholestan-3-on were investigated by gas chromatography and mass spectrometry. These derivatives are readily prepared and well suited for gas chromatographic analysis. In the mass spectrum they show fairly intense fragmentation, which appears to be characteristic for some structural elements in the surroundings of the functional group (excluding stereochemistry). This fragmentation may be useful for the structure elucidation of 3-oxo-steroids and related compounds. For comparison purposes the corresponding enolacetates were also investigated.     

Zum Einfluß von Zusätzen auf die Hydratation von Tricalciumsilicat (Ca3SiO5)

On the Influence of Admixtures on the Hydration of Tricalcium Silicate (Ca₃SiO₅) The influence of several compounds (alcohols, ketones, organic acids and the ir salts, cation exchange resin) on the hydration of tricalcium silicate was investigated by means of differential calorimetric analysis (DCA). The acceleration and retardation of this reaction found in these experiments are discussed on the basis of Ca(OH)₂ solubility, the pH of the solution and the rate of conversion of a C? S? H rich in CaO into a C? S? H poor in CaO at the surface of the C₃S grains.     

Reaktionen von 5H-1,2λ5-Azaphospholen mit Arylazocarbonitrilen sowie Acetylendicarbonsäure-estern

Reactions of 5H,2λ⁵-Azaphospholes with Arylazocarbonitriles and Dialkyl Acetylenedicarboxylates Azaphospholes 1a – c react with activated arylazocarbonitriles to 1,5,2λ⁵-diazaphosphorines 2a – c and 3a – c . The reaction of 1a – c with diethyl or dimethyl acetylenedicarboxyiates yields 7H-1,4λ⁵-azaphosphepines 4a – c . The structures of 2b , 3a , and 4a are established by an X-ray diffraction analysis.     

Zur Kristallstruktur von α-Li5AlO4

α-Li₅AlO₄ is isotopic to α-Li₅GaO₄ according to single crystal investigation and crystallizes orthorhombic, space group Pbca, with a = 9.087, b = 8.947, c = 9.120 Å and Z = 8.     

Reaktionen und Verknüpfungen von 1,2-Diaza-3-sila-5-cyclopentenen

Reactions and Bridging of 1,2-Diaza-3-sila-5-cyclopentenes 1,2-Diaza-3-sila-5-cyclopentenes react with butyllithium to give lithium salts. In reactions of the lithium salts with halosilanes ( 1–7 ), trimethyltinchloride (8) or methyliodide ( 9 ) substituted compounds are obtained by LiHal elimination. Bromosuccinimide brominates the methylene group of the ring system ( 10 ). Bridging of 1,2-diaza-3-sila-5-cyclopentenes by boryl and silyl groups are described ( 11–13 ). In the reaction of trifluorophenylsilane with lithiated 1 , 2-tert.-butyl-4-lithio-3,3,5-trimethyl-4-fluorodimethylsilyl-1,2-diaza-3-sila-5-cyclopentene, which is stable in solution, a second substitution takes place ( 14 ). The thermal elimination of LiF from lithiated 1 leads to the formation of the spirocyclic compound 15 . The n.m.r. and mass spectra of the compounds are reported.     

Die Kristallstruktur von Stickstofftrijodid-1-Pyridin NJ3 · C5H5N

The Crystal Structure of Nitrogen Triiodide-1-Pyridine NI₃ · C₅H₅N The crystal structure of NI₃ · C₅H₅N like “Nitrogen Triiodide” NI₃ · NH₃ contains NI₄ tetrahedra as essential structure elements. The tetrahedra are connected by common corners, forming indefinite chains. The pyridine molecule is bonded by its lone electron pair to one of the two iodine atoms that do not participate in the connection of the tetrahedra. Different from NI₃ · NH₃ there are very weak intermolecular interactions between iodine atoms of neighbouring chains.