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1.
    
The diversity of products in the reaction of diethyl azodicarboxylate (DEAD)/diisopropyl azodicarboxylate (DIAD) and activated acetylenes with PIII compounds bearing oxygen or nitrogen substituents is discussed. New findings that are useful in understanding the nature of intermediates involved in the Mitsunobu reaction are highlighted. X-ray structures of two new compounds (2-t-Bu-4-MeC6H3O)P (μ-N-t-Bu)2P+[(NH-t-Bu)N[(CO2]-i-Pr)(HNCO2-i-Pr)]](Cl-)(2-t-Bu-4-MeC6H3OH)(23)and [CH2(6-t-Bu-4-Me-C6H2O)2P(O)C(CO2Me)C-(CO2Me)CClNC(O)Cl] (33) are also reported. The structure of23 is close to one of the intermediates proposed in the Mitsunobu reaction.  相似文献   
2.
A capillary GC method employing an internal standard has been developed and successfully used for quantitative determination both of the raw materials used for the manufacture of m-phenoxybenzaldehyde and for the components of the reaction mixtures obtained at various stages of the development of the process. A complete analysis can be performed in a single temperature programmed run.  相似文献   
3.
The perovskite La2MnZnO6 has been synthesized by a ceramic technique and its catalytic activity has been tested for 2-propanol decomposition. The catalyst is totally selective to dehydrogenation of the alcohol. A possible mechanism for the reaction is proposed.
La2MnZnO6 2-. . .
  相似文献   
4.
Decomposition of N2O has been studied on pure La2CuO4, La2CuO4 with 5 and 10 wt. % LaNi5 and oxidized LaNi5 in the temperature range of 240–490 °C at 50 and 200 Torr initial pressures of N2O. The addition of LaNi5 decreases the energy of activation compared to that of La2CuO4 which has been explained based on the dispersity of NiO over La2CuO4.
N2O La2CuO4 La2CuO4 LaNi5 5–10 .%, 240–490°C N2O 50 200 . LaNi5 , . NiO La2CuO4.
  相似文献   
5.
Catalytic decomposition of N2O has been studied over a series of solid solution La2CuxZn1–xO4 (02O, in the temperature range 330–490°C. The observed trends in the kinetics have been explained based on polaron hopping mechanism. Parallel variation between activity and magnetic susceptibility has been observed.
N2O La2CuxZn1–xO4 (02O 200 330–490°C. . .
  相似文献   
6.
Decomposition of N2O has been studied over La2Cu0.5M0.5O4 (M=Co, Ni, Cu and Zn) between 380 and 485°C at 50 torr initial pressure of N2O to understand the mutual interaction of two different active metal ions of the same concentration and valence in deciding the physico-chemical and catalytic properties. A multicenter type of adsorption of N2O has been visualized and it is found that the rate is governed by the electronic factor.
N2O La2Cu0,5M0,5O4 (M=Co, Ni, Cu Zn) 380–485°C N2O, 50 . , - . N2O. .
  相似文献   
7.
8.
Compton spectrum due to L-shell electrons of thorium has been measured by the coincidence technique, using 279 keV incident gamma photons. The influence of L-shell electron momenta on the distribution of the scattered photons has been studied with reference to the Compton profile due to free electrons and compared with the exact and impulse hydrogenic theoretical models. Significant deviations are found between experimental and theoretical Compton spectra.  相似文献   
9.
10.
Abstract

Hydrolysis of several cyclic aminophosphites are discussed and compared with that of cyclic chloro/ phenoxy phosphites. An X-ray structure of a hydrolysis product, (C6H11NH3)+O?P(O)(H)(2,2′-OC6H4-C6H4OH) has been determined.  相似文献   
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