Die Titration von Sauerstoff und Antioxydantien mittels freier 2,4,6-Tri-tert.-butylphenoxy-Radikale

Ohne Zusammenfassung     

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.     

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).     

Das Verhalten des 2,4,6-Tri-tert.butylphenyllithiums gegenüber Halogensilanen. Bildung und Umwandlung des Trichlorsilyllithiums,LiSiCl3

The Behaviour of 2,4,6-Tri-tert.butylphenyllithium towards Halosilanes. Formation and Conversion of Trichlorosilyllithium, LiSiCl₃ Trichlorosilyllithium, LiSiCl₃ 2 , is formed as the result of a fast metal halogen exchange reaction at ?78°C in THF between 2,4,6-tri-tert.butylphenyllithium 1 or mesityllithium and bromotrichlorosilane. Also the interaction of 1 with trichlorosilane gives 2 after partial deprotonation of HSiCl₃. 2 is not isolated; it's existence in the THF solution is proved by protonation or deuteration, resp., and by identification of the HSiCl₃ or DSiCl₃ formed that way by means of ¹H-NMR or infrared spectroscopy. Attempts to react 2 with various electrophiles failed; also efforts to trapp dichlorosilylene, the expected decomposition product of 2 , by isoprene, were unsuccessful. Studies of the thermal decomposition of LiSiCl₃–THF solutions led to the identification of polychloropolysilanes and of insertion products of SiCl₂ in tetrahydrofuran.     

Benzooxaza- und Benzodiaza-λ3-phosphole und deren Reaktion zu spirocyclischen λ5-Phospholen

Benzooxaza- and Benzodiaza-λ³-Phospholes and their Conversion to Spirocyclic λ⁵-Phospholes 2,3-Dimethyl-1,3,2λ³-benzooxazaphosphole and 1,2,3-trimethyl-1,3,2λ³-benzodiazaphosphole are obtained by transamination of methylbis(dimethylamino)phosphane with N-methyl-o-aminophenol and N,N′-dimethylamino-o-phenylenediamine. These compounds are converted by oxidation and disproportionation reactions to spirocyclic λ⁵-phospholes. The crystal structure of 2-methyl-2,2′-spirobi(1,3-dimethyl-1,3,2λ⁵-benzodiazaphosphole) is established and a trigonal bipyramidal geometry of the molecule has been found.