Copper derivatives

S-hydroxyquinoline, oxine, C9H7ON. Light brown needles, m.p. 15-16 C. Forms insoluble complexes with metals. The solubilities of the derivatives vary with pH, etc. and hence oxine is widely used in analysis. Used for estimating Mg, Al, Zn and many other metals. Many oxinates are extracted and the metal is estimated spectrophotometrically. Derivatives, e.g. 2-meIhyl tend to be specific, for, e.g.. Copper derivatives are used as fungicides. 

Amongst the metals (M) investigated the copper derivatives are said to melt with decomposition at 380°C. 

House investigated the role of cuprous ions in the conjugate addition of organometallic reagents. He found that the catalytic effect can be explained by the intervention of a methyl copper derivative, which reacts rapidly with the carbon-carbon double bonds of the conjugated system. 

Remarkably, balogeti-magnesium exdiatige can also be extended to aryl and beteroaryl bromides [24, 25]. Tlius, tlie functionalized aryl bromides 28 and 29 iSdieme 2.7) were converted, at 0 C and at -30 C, respectively, into tlie corte-sponding Grignatd reagents. After treatment witli CuCN, tlie copper derivative 30 and 31 were obtained. Subsequent treatment witli typical electropb des sudi as benzoyl bromide or aliyl bromide fiirnisbed tlie products 32 and 33, in 70 and 8096 yields. 

Frykholm, K. O., Frithiof, L. Fernstrom, A. I. B., Moberger, G., Blohm, S. G. and Bjorn, E. Allergy to Copper Derived from Dental Alloys as a Possible Cause of Oral Lesions of Lichen Planus Acta Dermatovenerol, 49, 268-81 (1969)... 

The mother liquor contains only 2-3 g. more of the diketone, which can be separated as the copper derivative by shaking an ethereal extract with a saturated aqueous solution of copper acetate,... 

Scheme 8.1 Mixtures of gold and copper derivatives studied.

Silver acetylide is a more powerful detonator than the copper derivative, but both will initiate explosive acetylene-containing gas mixtures [1]. It decomposes violently when heated to 120-140°C [2], Formation of a deposit of this explosive material was observed when silver-containing solutions were aspirated into an acetylene-fuelled atomic absorption spectrometer. Precautions to prevent formation are discussed [3], The effect of ageing for 16 months on the explosive properties of silver and copper acetylides has been studied. Both retain their hazardous properties for many months, and the former is the more effective in initiating acetylene explosions [4],... 

The reaction between the copper derivative of pentafluorobenzene and chloracetyl chloride (ammonia as base) produces a little of the highly stable furan 8, an unusual result that has been regarded very tentatively as a Feist-Benary reaction with Cf,F5COCH2Cl as substrate.48... 

We owe to Kato and his colleagues a considerable advance in furan copper reagents. They have demonstrated the formation of the lithium di(3-furyl) cuprate species 87 which is highly reactive and possesses hard properties that suit it to reaction at hard centers, mainly carbonyl carbon.223 The reagent is easily prepared in situ from 3-furyllithium and Cu2I2. Simple copper derivatives do not react with ketones, but this cuprate reacts well and quantitatively with acid chlorides. It also reacts well with some epoxides (oxirans). Moreover, there is another form prepared in the presence of... 

Ethyl a-bromoisobutyrate, 21, 53 Ethyl /3-bromopropionate, 20, 6S Ethyl caprylate, 20, 69 Ethyl carbonate, 23, 95, 97 Ethyl chlorocarbonate, 21, 81 2-Ethylchromone, 21, 42 Ethyl diacetylacetate, 21, 46 copper derivative, 21, 46 Ethyl a,a-DIMETHYL-/3-PHENYL-/3-hydroxypropionate, 21, S3 Ethylene chloride, 20, 28 22, 76 ETHYLENEDIAMINE, IV IV-DIBUTYL-, 23, 23... 

Diethyl benzoylmalonate has been prepared by treatment of the copper derivative of ethyl benzoylacetate with ethyl chlorocarbonate.9 It... 

The C-H bond in CBnHi2 and related anions can be metallated by butyllithium and then converted into C-substituted anions with aldehydes, alkyl halides, Ph3SiCl, and Ph2PCl.322-329 C-halogenated (F,Cl,Br, or I) derivatives are made from the C-copper derivative with (PhS02)2NF or the corresponding N-halosuccinimide.330 The l-Me-2,3>4,5,6,7,8,9,10,ll>12-Fu-CBii- anion is made from the reaction of the corresponding Fn anion with... 

Francis placed strips of the retina from different animals in sodium sulphate to precipitate the cholinesterase in situ. Some strips were then incubated with acetylthiocholine, while others were kept in D.F.P. solution before the incubation. The tissues after preliminary washings were then treated with appropriate reagents so as to precipitate the copper derivative of thio-choline. The sections ultimately obtained showed dark deposits at those points where the enzyme was present, and deposits were absent if D.F.P. had destroyed the enzyme. As a result of the application of this technique, Francis was able to establish that for all the animals examined, except the frog, true cholinesterase was present only at the inner synaptic layer. 

Catalytic forms of copper, mercury and silver acetylides, supported on alumina, carbon or silica and used for polymerisation of alkanes, are relatively stable [3], In contact with acetylene, silver and mercury salts will also give explosive acetylides, the mercury derivatives being complex [4], Many of the metal acetylides react violently with oxidants. Impact sensitivities of the dry copper derivatives of acetylene, buten-3-yne and l,3-hexadien-5-yne were determined as 2.4, 2.4 and 4.0 kg m, respectively. The copper derivative of a polyacetylene mixture generated by low-temperature polymerisation of acetylene detonated under 1.2 kg m impact. Sensitivities were much lower for the moist compounds [5], Explosive copper and silver derivatives give non-explosive complexes with trimethyl-, tributyl- or triphenyl-phosphine [6], Formation of silver acetylide on silver-containing solders needs higher acetylene and ammonia concentrations than for formation of copper acetylide. Acetylides are always formed on brass and copper or on silver-containing solders in an atmosphere of acetylene derived from calcium carbide (and which contains traces of phosphine). Silver acetylide is a more efficient explosion initiator than copper acetylide [7],... 

It is not surprising that in attempted AICI3 catalysis of the reaction between thiophenol and various lactones, considerable amounts of thianthrene were obtained from a side reaction (81JOC5163). A low yield of thianthrene itself was obtained by converting o-bromobenzene thiol into its copper derivative (66JOC4071), but a good yield of thianthrene-2,3,7,8-tetracarboxylic acid 83 was observed from a hot reaction between 84 with cuprous oxide in DMF (82MI5). The saturated o-chlorobenzene thiols, 85... 

Bis-oxazoline ligands can also be produced by oxidative coupling of the copper derivative of diastereoisomerically pure 306 (Scheme 145) . Further lithiations of the product 317, which was produced as single diastereoisomer, occur (as in Scheme 143) at the second site adjacent to the oxazoline, giving, for example, 318, despite the (presumably) less favourable stereochemistry of the lithiation step. Bisoxazolines 318 direct the asymmetric copper-catalysed cyclopropanation of styrene using diazoacetate. 

The enantioselective lithiation of anisolechromium tricarbonyl was used by Schmalz and Schellhaas in a route towards the natural product (+)-ptilocaulin . In situ hthi-ation and silylation of 410 with ent-h M gave ewf-411 in an optimized 91% ee (reaction carried ont at — 100°C over 10 min, see Scheme 169). A second, substrate-directed lithiation with BuLi alone, formation of the copper derivative and a quench with crotyl bromide gave 420. The planar chirality and reactivity of the chromium complex was then exploited in a nucleophilic addition of dithiane, which generated ptilocaulin precnrsor 421 (Scheme 172). The stereochemistry of componnd 421 has also been used to direct dearomatizing additions, yielding other classes of enones. ... 

In order to modulate the reactivity of intermediate 331, it was transformed into its copper derivative by treatment with copper(I) bromide or iodide in THF at —78 °C, and then was allowed to react with a,/3-unsaturated carbonyl compounds (to give compounds 343 resulting from a conjugated addition), acyl chlorides (to give ketones 344) and copper(II) chloride (to dimerize giving compounds 345) (Scheme 100)"° ". ... 

Among the early attempts of amination of lithium and copper enolates were those which involved formation of a-A-(Boc)- or A-(Alloc)amino-substituted carboxylic esters, A-acyloxazolidinones and diethyl phosphonates (Scheme 33) ° . a-Lithum or a-copper derivatives of these enolates were aminated using A-lithium derivatives of A-Alloc O-(mesitylenesulfonyl)hydroxylamine 3j, NHBocOTos 31 and NHAllocOTos 3m. 

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