Hydrazination ruthenium-carbon

Ruthenium-carbon/hydrazine Retention of halogen s. 19, 18 Rhodium/alumina Amines from ketones via oximes s. 18, 27... 

Ruthenium-carbon/hydrazine Amines from nitro compounds Retention of halogen... 

Hydrazine (s. a. Wolff-Kishner reduction) 19, 42 —/ruthenium-carbon 19,18 —> dihydroehloride as reagent 19, 84... 

Ruthenium catalysts, supported on a commercial alumina (surface area 155 m have been prepared using two different precursors RUCI3 and Ru(acac)3 [172,173]. Ultrasound is used during the reduction step performed with hydrazine or formaldehyde at 70 °C. The ultrasonic power (30 W cm ) was chosen to minimise the destructive effects on the support (loss of morphological structure, change of phase). Palladium catalysts have been supported both on alumina and on active carbon [174,175]. Tab. 3.6 lists the dispersion data provided by hydrogen chemisorption measurements of a series of Pd catalysts supported on alumina. is the ratio between the surface atoms accessible to the chemisorbed probe gas (Hj) and the total number of catalytic atoms on the support. An increase in the dispersion value is observed in all the sonicated samples but the effect is more pronounced for low metal loading. 

A mixture of well-known extractants, di-(2-ethylhexyl)phosphoric acid (HDEHP) and CMPO, in n-paraffin was used for the study of combined extraction of different actinides (americium, plutonium, and uranium) and lanthanides (cerium and europium) and their separation from fission products (cesium, strontium, ruthenium, and zirconium).54 Combined extraction of MAs and lanthanides was studied together with group separation of MAs from lanthanides by selective stripping with a solution of diethylenetriaminepentaacetic acid (DTPA), formic acid, and hydrazine hydrate. This solution strips only MAs, leaving lanthanides in the organic phase. Subsequently, the lanthanides are stripped using a mixture of DTPA and sodium carbonate. 

Triazole derivatives could be synthesized from different starting substrates. Various triazoles 155 were synthesized from nonactivated terminal alkynes 152, allyl methyl carbonate 153 and trimethylsilyl azide 154 in a [3 + 2] cycloaddition with the use of the Pd(0)-Cu(I) bimetallic catalyst <03JA7786>. The allyl group of 155 was efficiently deprotected by ruthenium-catalyzed isomerization followed by ozonolysis to give 4-substituted triazoles 156. a-Aminoacetophenones 157 were reacted with hydrazines in acetic acid to give an efficient... 

Cyano-derivatives can be readily obtained by a ruthenium-catalyzed addition of various hydrazines to terminal alkynes [89] in which the cyano carbon atom arises from the terminal alkyne carbon atom. The tris(pyrazolyl)borate (Tp) complex RuCl(Tp)(PPh3)2 (1 mol%) was found to be the most active catalyst, and N,N-dimethylhydrazine (5 equiv.) the best nitrogen source. The proposed mechanism involves the nucleophilic attack of the nitrogen nucleophile on the a-carbon of a vinylidene intermediate (Scheme 8.27). Proton migration in the resulting a-hydrazi-nocarbene, followed by deamination, would give the nitrile derivative and regenerate the catalytic species. 

Complex formation with flic substrate is the key stage of many catalytic processes. The formation of the following types of organometallic complexes is most typical in catalysis alkyl 7i-complexes, carbene complexes, n-complexes of substrates with the saturated bond (olefin, acetylene and allyl, complexes with carbon oxides), hydrazine complexes, and complexes with molecular oxygen and nitrogen. The structure of a ruthenium complex with CO2 obtained on the basis of an ab initio study is presented in Fig. 17.4. 

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