Copper Diacetate

Treatment of 9-oxabicyclo[3.3.1]nonan-l-ols 1014 with a combination of lead tetraacetate and copper diacetate affords 3-allenyl tetrahydropyran-2-ones 1015 via an alkoxy radical accelerated ((-fragmentation pathway (Equation 396) <2001TL2047>. 

Copper diacetate-catalyzed arylation of heterocyclic amines such as piperidine, tetrahydroisoquinoline 76101 or 1,6-diazacyclodecane 77104 by aryllead triacetates gave only modest to moderately good yields of the iV-aryl derivatives (Equation (76) and (77)). The reactions with aliphatic amines lead to particularly poor yields of the derived anilines101 (Equations (78) and (79)), although the arylation of cyclooctylamine 78 with an electron-rich aryllead triacetate afforded the aniline derivative 79 in a moderately good yield (52%) (Equation (80)).1O5 1O5a... 

A variety of azole derivatives reacted with />-tolyllead triacetate 58 in the presence of copper diacetate to afford the iV-monoaryl derivatives in good to excellent yields (Equations (82)—(84)). 106 106a 109 109a 110 Benzimidazole 80 was arylated in 98% yield by />-tolyllead triacetate. In the case of the 5-aminobenzimidazole 81, excellent chemoselec-tivity was observed in favor of the primary aromatic amine with exclusive formation of the iV-/>-tolylaminobenzimi-dazole 82 in 50% yield.110... 

Methylindole, imidazole, and various triazoles were also TV-arylated. In the case of 1,2,4-triazole 83, 1,2,3-benzotriazole and indole derivatives, good yields of the Ar-aryl derivatives were only obtained upon treatment of the sodium salt of the substrate with />-tolyllead triacetate 58 in the presence of copper diacetate at 50-90 °C (Equation (85)).110... 

O-Arylation of alcohols or phenols cannot be performed by copper diacetate-catalyzed reactions using aryllead triacetates as the source of the aryl ligand. However, Dodonov et at. reported that tetraphenyllead reacts with primary and secondary alcohols in the presence of copper diacetate to afford the derived O-phenyl ethers in moderate yields ranging from 1.25 to 1.8 mol. of ether per mole of the lead reagent (Equation (100)). Phenol and tert-butyl alcohol afforded lower yields of the ethers (0.72-0.95 mole per mole of the lead reagent).117... 

SYNS ACETATE de CLTVRE (FRENCH) ACETIC ACID, CUPRIC SALT COPPER(2+) ACETATE COPPER(II) ACETATE COPPER DIACETATE COPPER(2+) DIACETATE CRYSTALLIZED VERDIGRIS CRYSTALS of VENUS CUPRIC ACETATE CUPRIC DIACETATE NEUTRAL VERDIGRIS OCTAN MEDNATY (CZECH)... 

The /V-arylalions of aliphatic, heterocyclic or aromatic amines is achieved either by treatment with pentavalent triarylbismuth derivatives and catalytic copper species or by treatment with a trivalent triarylbismuthane and stoichiometric amounts of copper diacetate that acts both as an oxidant and as the catalyst305. 

Dodonov and coworkers reported the earliest examples of the reactions of simple aliphatic amines (5-20 equivalents) with triphenylbismuth diacetate (1 equivalent). These reactions were conducted with catalytic amounts of copper diacetate (0.01-0.02 equivalent) in THF and formed the arylamine in 60-85% yields (equation 76)306 - 308. 

In this case, the second A-arylation was slow and required 1.5 equivalents of bismuth reagent and 1 equivalent of copper diacetate. For example, the first arylation of (5)-valine took place in 1 day at room temperature to yield 85% product, but the second A-arylation required 14 days at room temperature to yield 69% product. However, no racemization of the amino acid ester was detected, and for this reason, this procedure offers an advantage over the palladium-mediated arylation of amines that racemize amino acids342. 

The reactions of triphenylbismuthane with amines are carried out in the presence of stoichiometric amounts of copper diacetate in methylene chloride for 18-24 h to give... 

The 0-arylation of hydroxyl groups is obtained by reaction either with pentavalent organobismuth and catalytic copper or by reaction with trivalent organobismuth and stoichiometric copper diacetate, acting as an oxidant. 

The arylation of lower aliphatic alcohols was observed when the copper-catalysed decomposition of triarylbismuth diacetate was carried out in simple alcohols, used as solvent (20 mL per mmole of bismuth reagent). The yields of alkyl aryl ethers (based on the bismuth reagent) ranged from 60 to 95% for primary and secondary alcohols, but only 9% were obtained in the case of t rt-butyl alcohol.Under stoichiometric conditions, the 0-phenylation of 3-p-cholestanol by triphenylbismuth diacetate (1 equiv.) was not significantly improved upon addition of copper diacetate. 5 Different copper compounds, such as Cu(OAc)2, CuCl2, CuCl or metallic copper, can be used as effective catalysts. 

The mono-O-phenylation reaction of glycols discovered by David and Thieffry presents some characteristic features which are not compatible with the postulated covalent bismuth intermediate. (see section 6.3.2) The reaction is solvent-selective (methylene dichloride under reflux), light-catalysed (no reaction in the dark), and presents an induction period (2 hours in the case of the phenylation of 2,2-dimethylpropan-l,3-diol). Addition of small amounts of copper diacetate had a marked effect on the reaction. The reaction became fast reaction times can be as short as 15 minutes. Moreover, the copper-catalysed reaction is no more solvent selective nor light-catalysed. ... 

Although there is no reaction between triphenylbismuthane and copper diacetate triphenyl-bismuthane can transfer a phenyl group to alcohols and phenols when a stoichiometric amount of copper diacylate is used. When primary or secondary alcohols, used in large excess, were treated with triphenylbismuthane in the presence of copper diacetate in the ratio Ph3Bi Cu(OAc)2 =1 2, without solvent in sealed ampoules, the 0-phenyl ethers were formed in 43-91% yields (based on the bismuth reagent), at a very slow rate (several days at room temperature). No reaction with phenol was described under these conditions. ... 

When a solution of 3,5-di-rerr-butylphenol in methylene dichloride was treated with triphenylbismuthane (1.2 molar equiv.) in the presence of various amounts of copper diacetate (up to 2 equiv.), no reaction was observed. However, when triethylamine (6 molar equiv.) was added to the mixture of 3,5-di-rerr-butylphenol, triphenylbismuthane (1.2 molar equiv.) and copper diacetate (2 molar equiv.), the 6>-phenyl ether was now obtained in a moderate 44% yield, after 10 hours at room temperature. 

The reaction of simple aliphatic amines with triphenylbismuth diacetate and copper diacetate (the ratio used being 5-20 1 0.01-0.02) in tetrahydrofuran led to good yields of the derived arylamine (60-85% based on the bismuth reagent). In the case of the phenylation of iVJV-diphenylamine, a very poor yield was (< 3%) of triphenylamine was realized.99... 

However, when the reaction is performed in methylene dichloride in the presence of catalytic amounts of metallic copper, the iV-monophenylated amine derivatives are obtained in preparatively useful yields. Phenylation of aliphatic and aromatic amines with triphenylbismuth diacetate and metallic copper (ratio 1 1.1 0.1) in methylene dichloride at room temperature led to good to high yields of the derived anilines (up to 96% based on the amine). In the case of less reactive substrates, use of copper diacetate instead of metallic copper as catalyst constitutes a more reactive system which allows the preparation of the A -phenyl derivatives in moderate yields. These yields can also be improved by performing the reaction at a higher temperature. 

A variety of substituted W arylpiperidines (110) were obtained by arylation of 4-oxopiperidines (109) with various tris(3-substituted phenyl)bismuthane and copper diacetate. 10 ... 

A number of amides, imides, ureas, carbamates and sulfonamides have also been efficiently arylated by the triphenylbismuthane-copper diacetate system, when a tertiary amine promoter, such as triethylamine or pyridine, was added. 104... 

Reaction of amines with alkyldiphenylbismuthane in the presence of a stoichiometric amount of copper diacetate afforded mixtures of the corresponding mono- and di-substituted amines, the alkyl group being first transferred, followed by the phenyl group. The transfer of two different substituents was explained by a disproportionation reaction of the alkyldiphenylbismuthane into trialkylbismuthane and triphenylbismuthane.m ... 

The reaction of tributylbismuthane or tribenzylbismuthane with alcohols or phenol in the presence of copper diacetate led to very poor yields of the alkylbutyl or alkylbenzyl ethers (10-20% based on the bismuth reagent), l ... 

Under the conditions suitable for the A -arylation of amidic nitrogen atoms, (see section 7.6.1), reaction of p-ketoanilides with 4-methylphenyllead triacetate (67) in the presence of sodium hydride and copper diacetate afforded only products of C-arylation (68), although in poor yields (11-33%). The a-aryl-p-ketoanilides are unstable in solution and easily oxidised by air to the a-aryl-a-ketoanilide (69), also isolated in modest yields (8-19%). 1 3... 

In the presence of copper diacetate, the reaction of pentaphenylantimony with methanol and other simple aliphatic alcohols took place under milder conditions to afford only e 0-phenyl ethers. Under these conditions, the products of oxidation were no longer formed. 

COPPER DIACETATE or COPPER(II) DIACETATE (142-71-2) Incompatible with acetylides, hydrazine, nitrates, mercurous chloride, strong acids. 

Synonyms Acetic acid, copper (2+) salt Acetic acid cupric salt Copper acetate Copper (II) acetate Copper (2+) acetate Copper diacetate Copper (II) diacetate Crystallized verdigris Crystals of Venus Cupric acetate (INCI)... 

Copper diacetate Copper (II) diacetate. See Copper acetate (ic)... 

Other Heteroatom Nucleophiles. Alcohols and carboxylic acids also add to metal-activated alkenes, and processes for the industrial conversion of ethylene to vinyl acetate and acetals are well established. However, these processes have not been extensively used with more cort5)lex alkenes. In contrast, a number of intramolecular versions of the processes have been developed, a few examples of which are given here. Allylphenols cyclize readily in the presence of palladium(II) to form benzofurans (eq 4). Catalytic amounts of palladium acetate can be used if the reaction is carried out under 1 atm of molecular oxygen with copper diacetate as cooxidant, or in the presence of tert-butyl hydroperoxide. If instead of palladium acetate a chiral jr-allylpalladium acetate complex is used, the cyclization proceeds to yield 2-vinyl-2,3-dihydrobenzofuran with up to 26% ee. ... 

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