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In the presence of deuterium oxide benzaldehyde (1a) and substituted benzaldehydes likewise possessing lowest triplet states of (n,w*) character yield formyl-deuteriated benzaldehydes by fast and efficient photoreactions. Quantum yields of formation of 7-deuterio benzaldehyde 1b in solvent acetonitrile-deuterium oxide 3:1 are 0.57 at 313 nm), 0.54 at 331 nm. 0.62 at 365 nm, and in acetone-deuterium oxide 3:1 0.87 at 313 nm. 0.83 at 334 nm and 0.91 at 365 nm. By-products. mainly meso- and dl-dihydrobenzoin and benzoin. are formed to a small extent only. On the basis of CIDNP measurements the mechanism of photodeuteriation is discussed.  相似文献   

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The existence of radical pairs during the photolysis and the thermolysis of substituted benzenediazonium tetrafluoroborates and hydroquinone in acetonitrile is shown by means of CIDNP. The reaction is assumed to occur via a one-electron-step to form first a radical pair consisting of phenyldiazene and p-benzosemiquinone. This radical pair is able to lose nitrogen either by photolysis or thermolysis and can lead either to a disproportionation or to various recombinations.  相似文献   

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Zusammenfassung 2,5-gleichsubstituierte, C-peralkylierte 4-Selenoxoimidazolidine (1–5) lassen sich glatt aus Ketoncyanhydrinen, NH3, H2Se und den den Cyanhydrinen zugrunde liegenden Ketonen darstellen.Durch Umsetzung von -Aminonitrilen (-Aminoacetonitril, -Aminoisobutyronitril und -Aminobenzylcyanid) mit Aldehyden oder Ketonen und H2Se können auch in 2- und 5-Stellung unterschiedlich substituierte 4-Selenoxoimidazolidine (1, 7–17) synthetisiert werden. Es werden die Salzbildung (Ag+, Cd++), die saure Hydrolyse, die Hydrierung mit LiAlH4 und die Oxydation mit H2O2/NaOH am Beispiel von C-peralkylierten 4-Selenoxoimidazolidinen beschrieben.Die aminkatalysierte Einwirkung von Schwefel auf ein 2,2-dialkyliertes 5-Phenyl-4-selenoxoimidazolidin führt zum entsprechenden Imidazolin-3-thion-(5).
Identically 2.5-substituted, C-peralkylated 4-selenoxoimidazolidines (1–5) may be obtained readily from ketone cyanohydrins, ammonia, selenium hydride and the ketones corresponding to the cyanohydrins.4-Selenoxoimidazolines, differently substituted in 2- and 5-positions may also be synthesised by the reaction of -aminonitriles, e.g. -aminoacetonitrile, -aminoisobutyronitrile or -aminobenzylcyanide, with aldehydes or ketones. Salt formation (Ag+, Cd++), acid hydrolysis, reduction with LiAlH4 as well as oxidation with NaOH/H2O2 have been described in the case of C-peralkylated 4-selenoxomidazolidines.


65. Mitt.:F. Asinger, H. Offermanns, P. Müller undH. Andree, Mh. Chem.99, 2059 (1968).

Teil der Dissertation vonH. Berding, Techn. Hochschule Aachen, 1966.  相似文献   

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Zusammenfassung Durch Methylierung von 8(14)-7-Oxo-thebainon-methaperchlorat (1) wird 4-O-Methyl-salutaridin-methoperchlorat (2) erhalten, das beimHofmannabbau das Methin3 liefert. Einwirkung von konz. HCl auf2 bei Raumtemp. führt zu 7-Hydroxy-4-O-methyl-7.8-dehydro-metathebainon-methoperchlorat (4 a), aus dem beim Erwärmen mit 10n-HClO4 7-Hydroxy-4-O-methyl-morphothebain-methoperchlorat (5) entsteht. Die Strukturen von2, 3, 4 a und5 werden bewiesen.
Preparation and reactions of 4-O-methyl-salutaridinemethoperchlorate
Methylation of 8(14)-7-oxo-thebainone-methoperchlorate (1) yields 4-O-methyl-salutaridine-methoperchlorate (2), which by action of 1n-NaOH is degradated to methine3. Acidic hydrolysis of2 at room temperature yields 7-hydroxy-4-O-methyl-7.8-dehydro-metathebainone-methoperchlorate (4 a), which by heating in 10n-HClO4 solution can be rearranged to 7-hydroxy-4-O-methyl-morphothebaine-methoperchlorate (5). The structures of the new compounds2, 3, 4 a, and5 are proved.


Herrn Prof. Dr.M. Pailer zum 60. Geburtstag gewidment.  相似文献   

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Reactions of Tetrafluoro-1, 2-ethanedisulfenyldichloride with Ketones and Olefines The reaction of ClSCF2CF2SCl 1 with (CH3)3C? C(O)CH3, hexene, diacetyl, cyclobutanone, and H2C?CHC(O)CH3 leads to the cyclic and acyclic products 2 – 6 . They are destillable liquids, which have been characterized on the basis of elemental analysis, mass spectra, 19F-, 13C-, and 1H-n.m.r. spectra. The reaction mechanism will be discussed.  相似文献   

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