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H. Biere  R. Russe 《Tetrahedron》1974,30(18):3513-3517
The total synthesis of the main human metabolite of a new antidiabetic drug is described along with some chemistry of 2-amino-pyrimidine derivatives. Structural confirmation of the products was obtained by spectroscopic examination.  相似文献   

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Synthesis of New Morphine Partial Structure 15,16-Secomorphinan The synthesis of a new morphine partial structure, 15,16-secomorphinan, is described. One of the series, (±)-15, 16-secocyclorphan (5) , has the analgesic potency of morphine and exhibits good binding to the opiate receptor.  相似文献   

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Synthesis and Characterization of a New Metallacyclic Compound of Osmium The bissilylated phosphorane, Me3SiNP(Ph2)CH2(Ph2)PNSiMe3 1 reacts with OsO4 via the migration of SiMe3 groups to give a new metallacycle 2 containing OsVIII. 1H, 31P, and 29Si n.m.r. spectroscopic investigations confirm the cyclic structure of 2 .  相似文献   

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Zusammenfassung Rh2(CO)4Cl2 reagiert mit Tribenzylamin und NaBH4 zu einer Verbindung, die als Tris-tribenzylaminrhodiumcarbonylhydrid charakterisiert wurde. Der Komplex katalysiert die Hydroformylierung bereits unter milden Bedingungen. Aus -Olefinen werden vorwiegend lineare Aldehyde gebildet.
Hydroformylation of olefins with a new rhodiumcarbonyl complex of tribenzylamine
Rh2(CO)4Cl2 reacts with tribenzylamine and NaBH4 forming a compound, which was characterized as hydridocarbonyltristri(benzylamine)rhodium(I). The complex catalyses the hydroformylation under mild conditions. Thus -olefins are converted predominantly into linear aldehydes.


Mit 4 Abbildungen

Herrn Prof. Dr.F. Asinger in Verehrung zum 65. Geburtstag gewidmet.  相似文献   

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Determination of carcinoembryonic antigen: Experiences with a new radioimmunoassay
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Zusammenfassung Für das Herbain wird die Strukturformel eines 11-Methoxy-16,17-dihydro-heteroyohimbans (1) abgeleitet. Außerdem wird die Identität des Vincaherbins mit Herbain und des Vincaherbinins mit Herbacein nachgewiesen.Mit 2 Abbildungen  相似文献   

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Hydroxide ion is shown to react with α-glucose in two ways. Firstly, it catalyses mutarotation of α-glucose in conjunction with the hydrate sheath, and secondly, it reacts extremely rapidly as partially dehydrated hydroxide ion with formation of α-glucosate ion without mutarotation of α-glucose. This knowledge, combined with the author's determination of the hydrogen bond entropy of the hydrated oxonium ion leads to new views on the mechanism of very rapid oxonium ion reactions. The hydrogen bond entropy of the hydrated oxonium ion ΔS was determined by the author from the coefficients of the water catalysisk W and oxonium ion catalysiskH3O+ of the mutarotation of α-glucose $$\Delta S = R ln {{k_w } \mathord{\left/ {\vphantom {{k_w } {k_{H_3 O^ + } }}} \right. \kern-\nulldelimiterspace} {k_{H_3 O^ + } }},$$ As the proton of the hydrated oxonium ion is attracted by both oxygen atoms with the same intensity, (ΔS)/2 is the hydrogen bond entropy of the single hydrated proton, which is to be considered as the activated oxonium ion of the reactions between the oxonium ion and the anions. While only the activation of the oxonium ion is necessary for the reaction of the oxonium ion with hydroxide ion, the reaction of the oxonium ion with acetate ion needs furthermore the activation of this anion, which consists of rupture of the internal hydrogen bond of this anion. The enthalpy of activation of the acetate ion is determined by the author from the acetate ion catalysis and the water catalysis of the α-glucose mutarotation. The activation enthalpy of the reaction of the oxonium ion with acetate is therefore the sum of the activation enthalpies of the oxonium ion and of the anion. Furthermore it is shown that the high migration velocity of the hydrogen ion in aqueous solution is due to the proton exchange between the water molecules, initiated by the single hydrated proton.  相似文献   

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