1, 2λ5-azaphosphinines and a new 1λ5, 3λ5-. Diphosphinine

The 1,2-azaphosphinine, 9 , and the 1,3-diphosphinine, 10 , can be isolated from a mixture resulting from the reaction of 1,1,3,3-tetrakis(dimethylamino)-1λ⁵,3λ⁵-diphosphete, 1 , and ethyl isothiocyanate. The reaction of 1 with phenyl isothiocyanate yields the 1,2-azaphosphinine, 16 . Mechanisms for the formation of the compounds 9 , 10 , and 16 are suggested. The properties, the NMR, mass, and IR spectra, and the molecular and crystal structures of 9 and 10 are described and discussed.     

Die Hydrolyse des 1, 1, 3, 3-Tetrakis(dimethylamino)-1λ5, 3λ5-diphosphets

Hydrolysis of 1,1,3,3-Tetrakis(dimethylamino)-1λ⁵, 3λ⁵ -diphosphete Hydrolysis of 1,1,3,3-Tetrakis(dimethylamino)-1λ⁵, 3λ⁵ -diphosphet ( 2 ) yields in the first step Bis(dimethylamino)phosphorylmethyliden-methyl-bis(dimethylamino)phosphorane ( 5 ). In the second step Bis(dimethylamino)phosphoryl-methyl(dimethylamino)phosphosphonylmethylen ( 6 ) is the main product of hydrolysis. In addition small amounts of methylphosphonic-bis(dimethylamide) ( 7 ) are formed. Properties, nmr and mass spectra of 5 and 6 are described, their mechanism of formation is discussed.     

Thermal [1, 3] benzoyl migration in 1-(α-benzoyloxyarylideneamino)-1,2,3-triazoles. Part II

1-(α-Benzoyloxyarylideneamino)-4, 5-dirnethyl-1,2,3-triazoles (V) were prepared by reacting the sodium salt of substituted 1-benzoylamino-4, 5-dimethyl-1,2,3-triazoles (IV) with benzoyl chloride at ?50°. The uncatalyzed thermal isomerization of isoimides V to the corresponding imides VI was studied kinetically and the reaction mechanism is discussed.     

Zum thermischen Verhalten von Li3MnO4. II [1, 2]. Über α- und β- Li2MnO3

Thermal Behaviour of Li₃MnO₄. II. α- and β-Li₂MnO₃ By thermal decomposition of Li₃MnO₄ we obtained two new forms of Li₂MnO₃: α-Li₂MnO₃ crystallizes due to Guinier-Simon photographs cubic face-centered with a = 4.09₂ Å, β-Li₂MnO₃ hexagonal with a = 4,93, c = 14.24 Å, c/a = 2.89. α-Li₂MnO₃ is paramagnetic with μ = 3,82 B.M. Below the Neel temperature (≈? 50 K) β-Li₂MnO₃ is antiferromagnetic. Effective Coordination Numbers, ECoN, are calculated and discussed.     

Fluoroazoles. III. Synthesis and 1H and 1–9F nmr spectra of 3-, 4-, and 5-fluoro-1-methylpyrazole

The three monofluoro derivatives of N-methylpyrazole have been synthesized. 3-Fluoro-1-methylpyrazole and 4-fIuoro-1-methylpyrazole were prepared from the appropriate amines by diazotization and photochemical irradiation of the diazonium salts in tetrafluoroboric acid. 5-Fluoro-1-methylpyrazole was obtained from 1-acetyl-3-fluoropyrazole and methyl fluorosulfonate, and also by direct methylation of 3(5) fluoropyrazole with dimethyl sulfate. The ^1–9F chemical shifts of these N-methylated fluoroazoles cover a great range (ca. 50 ppm) and show a good correlation with the chemical shifts of H₃, H₄, and H₅ protons of 1-methylpyrazole. An unexpected long-range coupling ⁵J (F-CH₃) is observed in 3-fluoro-1-methylpyrazole.     

3, 6-endoxocyclohexanes and -cyclohexenes. XXV. Some reactions of dimethyl 4,5-(1-benzyl-1, 2, 3-triazoline)-3, 6-endoxohexahydrophthalate

The anhydride and dimethyl ester of 4, 5-(1-benzyl-1, 2, 3-triazoline)-3, 6-endohexahydrophthalic acid, having a triazoline ring with an exo-cis configuration, are synthesized by reaction of benzyl azide with the furan-maleic anhydride adduct. Opening of the triazoline ring under the action of hydrochloric and acetic acids takes place with the separation of nitrogen and formation of the chloro and acetoxy derivatives, respectively, unaccompanied by a Wagner-Meerwein type of rearrangement.Part XXIV, see [1].     

Separation of (3R, 3′ R)-, (3R, 3′ S; meso)-, (3S, 3′ S)- Zeaxanthin, (3R, 3′ R, 6′ R)-, (3R, 3′ S, 6′ S)- and (3S, 3′ S, 6′ S)-Lutein via the dicarbamates of (S)-(+)-α-(1-naphthyl) ethyl isocyanate

A method is described for the qualitative and quantitative determination of configurational isomers of zeaxanthin (=3,3′ -dihydroxy-β, β -carotene) and lutein (=3,3′ -dihydroxy-α -cartotene). It is based on the reaction of these zeaxathin and lutein isomers with (S)-(+)-α-(1-naphthyl) ethyl isocyanate to afford diastereomeric dicarbamates, which are analyzed by HPLC.