Copper ethyl

Copper, (ethyl valinate-,V,.V-diacetato)diaqua-structure, 6, 421... 

At first it was thought that the copper methyl might react with the silicon halide in the manner of a Grignard reagent, but copper ethyl and copper phenyl prepared in ether suspension did not react with silicon tetrachloride. Neither did free methyl radicals from lead tetramethyl react with elementary, silicon, but they did add on silicon that was being chlorinated. This suggests that the third step in the mechanism is the addition of methyl groups to the chlorinated silicon formed in the cuprous chloride reduction ... 

Similarly, ra 5-cyclopropanes were obtained from alkenes, such as styrene and 2,5-dimethyl-hexa-2,4-diene, with relative yields > 90% when a diazoacetate bearing a bulky ester group was decomposed by a copper catalyst with bulky salicylaldimato ligands. Several metal complexes with bulky Cj-symmetrlc chiral chelating ligands are also suitable for this purpose, e.g. (metal/ligand type) copper/bis(4,5-dihydro-l,3-oxazol-2-yl)methane copper/ethyl-enediamine ruthenium(II)/l,6-bis(4,5-dihydro-l, 3-oxazol-2-yl)pyridine cobalt(III)/ salen. The same catalysts are also suited for enantioselective reactions vide infra). For the anti selectivity obtained with an osmium-porphyrin complex, see Section 1.2.1.2.4.2.6.3.1. 

Organometallic polymers with metals in the main chain can only be produced by polycondensation. In some of these reactions, the metal occurs in the monomer before the polycondensation step, e.g., in the reaction of copper ethyl acetoacetate derivatives with glycols ... 

Pure NaEtX Pure KBuX Pure KLM (EtX)2 Precipitate of copper ethyl xanthate Precipitate of cuprous ethyl xanthate Precipitate of lead ethyl xanthate Precipitate of zinc ethyl xanthate... 

The volatile hydrogen cyanide produced under these circumstances may be detected by the color reaction described on page 348 using copper ethyl-acetoacetate and tetrabase. 

In contrast to mercury cyanide, alkali cyanides are completely converted into alkaK cyanates when warmed with an excess of potassium permanganate with the precipitation of MnOg. The latter and the excess of KMn04 are destroyed by the addition of a drop of hydroxylamine hydrochloride and a drop of 2 iV hydrochloric acid. At this stage, Hg(CN)2 releases hydrogen cyanide which can be detected by the copper ethyl acetoacetate-tetrabase test described on page 348. In this way, starting with a drop of the test solution, 2 y of Hg(CN)2 can be detected in the presence of 500 y of alkali cyanide. 

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