Ethyl-metal derivatives

See Ethyl diazoacetate Tris(dimethylamino)antimony See Other IV-METAL DERIVATIVES... 

UV/Vis spectroscopic titrations were used to determine association constant data for the calix[4]arenediquinone ligands with metal and ammonium cations and the results are summarized in Table 11. For both [54] and [55], Na+ and Ba2+ cations form very stable complexes. It is noteworthy that the diamide calix[4]arenediquinone [55] exhibits a larger association constant for BUNH3 than for NH, whereas with the bis(ethyl ester) derivative [54] the reverse... 

Eliminations from Os(CO)4RR occur by dinuclear mechanisms only if either R or R is H. A hydride on one metal is necessary to interact with a vacant coordination site on the other in the dinuclear transition state. With Os(CO)4H2, the vacant site is created by dissociation of CO. With Os(CO)4-(H)CH the vacant site is created by a facile rate-determining isomerization which we suggest is to an acetyl hydride. The unique instability of hydridoalkyl carbonyls thus is explained. The synthesis and properties of Os(CO)4(H)C2H and various polynuclear ethyl osmium derivatives show that (3-hydrogens have no significant effect on these elimination mechanisms. Dinuclear hydridoalkyls are excellent starting points for the synthesis of more complex polynuclear alkyls. 

The alkylation of pyrazylmethylsodium with jS-dimethylamino-ethyl chloride gives l-pyrazyl-3-dimethylaminopropane (28).178 Compound 28 forms the expected metalated derivative on treatment with sodamide and liquid ammonia and this with ketones gives carbinols,179 and with esters yields ketones (e.g., 29).181 Reaction of pyrazylmethyl sodium with A-methyl-A-phenylcyanamide gives pyrazylacetonitrile.182... 

Treatment of P-carbonyl sulfoximines 296 (R=Bu , CO,Me, N(Pri)2) with diethylzinc gave the corresponding ethyl zinc derivatives.12 The X-ray crystal structure of the ethyl zinc derivative (R=Bu ) showed a dimeric 0-metallated... 

Chloropyrazine and derivatives have been shown to react with alkali metal derivatives of a phenylacetonitrile or of a phenylacetamide for example, 2-chloropyrazine treated with diphenylacetonitrile in toluene with sodium amide gave 2-(T-cyano-r,r-diphenylmethyl)pyrazine (68, R = H) (1021, 1022). 2-Chloro-5-phenylpyrazine(s) with diethyl methylmalonate and sodium hydride gave 2-(r,l -di(ethoxycarbonyl)ethyl]-5-phenylpyrazine(s) (363-365, 824, 825), and a similar reaction occurred with 2-chloropyrazine (364, 365,1023). 

An example of a polyamine dendrimer functionalised by 2-pyridylethyl- substituents is (167).269 The interaction of (167) with copper(II) acceptors gives metal derivatives containing one metal for each bis[2-(2-pyridyl)ethyl]amine moiety. (167) is found to bind approximately 32 Cu ions. Polyamidoamine species containing Cu ions can be reduced in solution to zerovalent copper nanoclusters, providing a metal nanocomposite.270 Such copper(O) solutions are stable for several months, owing to the surface properties of the host dendrimer molecules. 

Recently, Chen has synthesized and resolved chiral suberyl carbenium ions and utilized these as catalysts for enantioselective Mukaiyama aldol addition reactions (Eq. (8.22)) [34]. Thus the reaction of the ethyl acetate-derived silyl ketene acetal with benzaldehyde in the presence of 10-20 mol% of catalyst afforded the corresponding adduct in 50% ee. The enantioselectivity of the process proved sensitive to the nature of the cation, consistent with observations previously highlighted by Denmark in related studies [35]. Although at the current level of development the selectivities are modest, the study documents a novel class of metal-free Lewis acidic agents. 

Kirilov, M., Ivanov, D., Petrov, G., and Golemshinski, G., Phosphonation of polyfunctional organometallic reagents. Part 1. Metal derivatives of phenylacetic acid and its ethyl ester. Bull. Soc. Chim. Fr., 3051, 1973. 

The effect of heavy atoms on the relative yields of fluorescence and phosphorescence has been investigated both by inserting Br and I substituents in the ring of deuterioporphyrin IX and its Zn derivative,340 and by adding ethyl iodide to the solution of a number of free base porphyrins.341 Other authors discuss the luminescence of protoporphyrin IX dimethylester after pulse radiolysis in benzene,848 and from monomeric and dimeric ethylenediamine-substituted protoporphyrin IX and some metal derivatives.343 Several reports consider the emission from porphyrins in Shpolskii matrices and other crystalline organic hosts.344-340... 

The alkyl substitution-products of acetoacetic ester, which can be prepared by the methods just described, react with sodium ethylate and form metallic derivatives —... 

Other protein-rhodium conjugates containing cationic rhodium catalysts have also been prepared using bis(diphenylphosphino-ethyl)amino derivatives 5-7 and solutions of these bis(phosphine) ligands in the presence of carbonic anhydrase, a-chymotrypsin and bovine serum albumin (47). However, the exact nature of the complexes formed has not been discerned in any of these cases, and these latter enzyme-transition metal complexes evidently do not exhibit enantioselectivity in hydrogenation of a-acetamidoacrylic acid. 

The use of metalloporphyrins as cyclopropanation catalysts originated with Callot who reported that (TPP)Rhl provided a cis preference for the cyclopropanation of styrene with ethyl diazoacetate (Scheme 15) [158,159]. This was quite unexpected because cyclopropanation of cis-olefin using diazoesters and metal derivatives as catalysts usually gives the trans cyclopropyl ester as the major product [167]. The cis-selectivity increased with the size of the substituents at the meso position and suggested a preferential direction of approach of the alkene towards a rhodiiun carbene complex [159]. 

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 ... 

Di-ethylbenzenechromium reacts with alkyl halides such as ethyl iodide and results in the oxidation of the central metal of the complex and the disproportionation of ethyl radicals derived from ethyl iodide, equation (6-45). 

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