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Substituted 1,1′-diester, diketone and dinitrile derivatives are prepared from 2,2′-biimidazole. The reactions involved include: Michael addition with halogenated olefins; nucleophilic substitution with ketones, nitriles, and esters; and condensation with amines.  相似文献   
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The reaction of Ir6(CO)16 with a mixture of CO, H2, and ethylene yields the [Ir6(CO)15COEt]- anion, which has been shown by X-ray diffraction to contain an octahedral iridium cluster bearing a —bonded acyl group; the arrangement of the 11 terminal and 4 edge-bridging carbonyl groups is different from that found in both the analogous rhodium complex and the parent Ir6(CO)16 carbonyl.  相似文献   
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Abstract

It is known that pressure alone is not able to make shelf-stable any food stored in room conditions. Acid products are normally spoiled by enzymes, and low acid products are spoiled even by spore-forming micro-organisms. To overcome the problem the role of heat in the process has been re-evaluated and the possibility of destroying at the same time spores and enzymes has been found. This work compares the effect of sterilisation by High Pressure Processing (HPP) with one of the conventional retort processing techniques. Two batches of meat sauce were kept in room conditions over a year and their quality was evaluated periodically during the shelf life simulation. The physico-chemical characteristics of the retorted ones showed a progressive appearance of the typical thermal damage. The High Pressure Sterilised samples on the contrary showed limited damage, related to the unavoidable pre-heating. Their quality markers were constant over the shelf life evaluated period.  相似文献   
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A new, simple and short route to 2-alkylcyclopent-2-enones starting from inxpensive terminal epoxides is described.  相似文献   
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The new mixed PtRh cluster trianion [Pt2Rh9(CO)22]3? has been isolated as a minor product of the pyrolysis of [PtRh5(CO)15]?, and has been characterized by X-ray diffraction. The metal skeleton, which has ideal D3h symmetry, consists of three face-to-face condensed octahedra, as previously found in the isoelectronic species [Rh11CO)23]3?, with the Pt atoms on the three-fold axis, in the positions of maximum MM connectivity.  相似文献   
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Secondo P  Fages F 《Organic letters》2006,8(7):1311-1314
[reaction: see text] The first examples of bismacrocyclic derivatives of 2,3,6,7,10,11-hexaphenyl-1,4,5,8,9,12-hexaazatriphenylene are described. They are obtained by the condensation of a linear trisbenzil precursor with hexaaminobenzene.  相似文献   
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We identify ?ech cocycles in nonabelian (formal) group cohomology with Maurer–Cartan elements in a suitable L -algebra. Applications to deformation theory are described.  相似文献   
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