Azoperoxide. VII. Thermolyse von α-Alkylazo-alkylhydroperoxiden

Azoperoxides. VII. Thermolysis of α-Alkylazoalkylhydroperoxides The thermal decomposition of 1-methylazo-1-hydroperoxycyclohexane 1 and 1-tert.-butylazo-1-hydroperoxycyclohexane 2 was studied in ethylbenzene and in the case of 2 also in other solvents. Decomposition products and decomposition rates of the azo and the peroxy groups were selectively estimated. The title compounds decompose faster than the analogous azo compounds and alkylhydroperoxides. A induced homolysis of both initiator groups is proposed; the compounds are not „bifunctional initiators”︁.     

β-Fur-2-yl-α-halogenacrylonitrile. I. Darstellung von β-Fur-2-yl-ß-aminoacrylonitrilen und β-Fur-2-yl-α-aminoacrylonitrilen

β-Fur-2-yl-α-halogenacrylonitriles. I. Preparation of β-Fur-2-yl-ß-aminoacrylonitriles and β-Fur-2-yl-α-aminoacrylonitriles β-Fur-2-yl-α-halogenacrylonitriles 1 react with secondary amines to yield β-fur-2-yl-ß-aminonitriles 2 and β-fur-2-yl-α-aminoacrylonitriles 3 . The ¹ H-n.m.r. spectra of the E/Z isomers are discussed.     

Synthese von β-Nitroalkenyl-benzylphosphorylderivaten

Synthesis of β-Nitroalkenyl-benzylphosphorylderivatives Starting from methoxy-chlormethylbenzaldehydes 2 the benzylphosphonates and -phosphinoxides 3 A, B had been synthesized, which could be transformed via the Schiff-bases 4 A, B to phosphorylated nitrostyrenes 5 A, B and nitropropenylbenzenederivatives 6 A, B . The phosphonoacids 3 Ad, 3 Bd and 6 Ba could be prepared from the corresponding esters by direct acidic hydrolysis or by dealkylation with trimethylsilylbromide and hydrolysis of the trimethylsilylesters respectively.     

Partialsynthesen von Cardenoliden und Cardenolid-Analogen. I. α,β- und β,γ-ungesättigte Lactonring-methylierte Cardenolide

Partial Syntheses of Cardenolides and Cardenolide Analogues. I. α,β- and β,γ-Unsaturated Lactone Ring-Methylated Cardenolides Base-catalyzed methylation of digitoxigenin 1a with methyl iodide and sodium hydride in DMF leads to the α,β-unsaturated cardenolides 2–5 and, after rearrangement of the CC-double bond, to the β,γ-unsaturated cardenolides 6 and 7 . Opening of the lactone ring results in the formation of 8 . Allylic oxidation of 4b affords the 14,21-epoxide 10 . Only the 22-methyl derivative 4a and its 3-O-tridigitoxoside 4d show strong biological effectivity, whereas methylation at 21R- or 21S-position results in considerable loss in activity.     

Synthesen von β-Fur-2-yl-α-halogenacrylonitrilen

Syntheses of β-Fur-2-yl-α-halogenacrylonitriles Syntheses of β-fur-2-yl-α-halogenacrylonitriles 2a–f by Wittig-olefination of furfurales, Hunsdiecker-reaction of β-(5-nitro-fur-2-yl)-α-cyanoacrylic acid 3 , halogenation of β-fur-2-yl acrylonitriles and reaction of furfurales with β-azido-α-halogen-γ-methoxy-Δ^α,β-crotonolactones 9 are described.     

β-Fur-2-yl-α-halogenacrylonitrile. IV. Reaktionen von β-Fur-2-yl-α-halogenacrylonitrilen mit Alkoholen und Phenolen

β-Fur-2-yl-α-halogenacrylonitriles. IV. Reactions of β-Fur-2-yl-α-halogenacrylonitriles with Alcohols and Phenols β-Fur-2-yl-α-halogenacrylonitriles 1a – c react with alcohols and phenols to yield β-fur-2-yl-β-alkoxyacrylonitriles and β-fur-2-yl-β-aroxyacrylonitriles 2a – k respectively. With ethylene glycol α-[2-(fur-2-yl)-1, 3-dioxolan-2-yl]acetonitriles 3a, b are formed.     

β-Thiocyanatovinylcarbonylverbindungen. XI. Ungewöhnliche Substituenteneffekte bei der massenspektrometrischen Fragmentierung von β-Thiocyanatovinylaldehyden

β-Thiocyanatovinylcarbonyl Compounds. XI. Unusual Substituent Effects in the Mass-spectrometrical Fragmentation of β-Thiocyanatovinylaldehydes The mass spectra of homologous Z/E-isomers and constitutional isomers of β-thiocyanatovinylaldehydes are discussed. The main fragmentation consisting of HCN-loss from the molecular ion is influenced by the substituents so that the constitutional and steric isomers can be clearly distinguished by the \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm M - HC}\left. {\overline {\, {\rm N} \,}}\! \right| + /{\rm M + }^ \cdot $\end{document} ratio. Alkyl homologues with a hydrogen atom in γ-position to the aldehyde group show an unusual intensive CN-radical loss due to a „hidden hydrogen rearrangement”︁, which was proved by deuteration experiments.     

Furylvinylhalogenide. IX. Reaktionen von β-Fur-2-yl-β-chlor-α-cyanacrylsäureestern mit Aminen

Furylvinylhalides. IX. Reactions of β-fur-2-yl-β-chloro-α-cyanoacrylates with amines β-Fur-2-yl-β-chloro-α-cyanoacrylates 4 react with amines to yield β-Fur-2-yl-β-amino-α-cyanoacrylates 5 . The ¹H-n.m.r. spectra of 5 are discussed.     

P-Funktionalisierung von β-Nitrostyrolen mit Trialkylphosphiten

P-Functionalization of β-Nitrostyrenes by Means of Trialkylphosphites α-Aryl-β-nitroethanephosphonates, which hardly are accessible by base-catalysed addition of dialkylphosphites, can be prepared from β-nitrostyrenes by protic addition of trialkylphosphites.