Copper aliphatic amines

Primary, secondary, and tertiary aliphatic amines have been cleaved to give aldehydes, ketones, or carboxylic acids with aqueous bromine and with neutral permanganate. The other product of this reaction is the amine with one less alkyl group. In a different type of procedure, primary alkyl primary amines can be converted to ge/n-dihalides, RCH2NH2 —> RCHX2 (X =Br or Cl), by treatment with an alkyl nitrite and the anhydrous copper(I) halide. 

A list of structurally characterized copper(I) complexes of tripodal aliphatic amines is provided in Table 4 (cf. Section 6.6.3.1.1 for corresponding mononuclear or dinuclear copper(II) complexes). Copper(II) complexes [(L)CuCl]Cl (664) and [(L)Cu(MeCN)][C104]2 (665) with the ligand that is present in complex (662) were also structurally characterized.522... 

Another situation is observed when salts or transition metal complexes are added to an alcohol (primary or secondary) or alkylamine subjected to oxidation in this case, a prolonged retardation of the initiated oxidation occurs, owing to repeated chain termination. This was discovered for the first time in the study of cyclohexanol oxidation in the presence of copper salt [49]. Copper and manganese ions also exert an inhibiting effect on the initiated oxidation of 1,2-cyclohexadiene [12], aliphatic amines [19], and 1,2-disubstituted ethenes [13]. This is accounted for, first, by the dual redox nature of the peroxyl radicals H02, >C(0H)02 and >C(NHR)02 , and, second, for the ability of ions and complexes of transition metals to accept and release an electron when they are in an higher- and lower-valence state. 

Primary aliphatic or aromatic amines RNH2 are converted into carbamates RNHCC Et on treatment with carbon monoxide and di-t-butyl peroxide in the presence of palladium(II) chloride and copper(II) chloride357. Carbamic esters 304 and 305 are also obtained from aliphatic amines and ortho carbonates (R30)4C358. Vinyl carbamates R12NC02CH=CHR2 are produced from secondary aliphatic amines, acetylenes R2C=CH (R2 = Bu or Ph) and carbon dioxide in the presence of ruthenium(III) chloride359. 

As a consequence of the detection of catalytic pathways for formation of PCDD/F, special inhibition methods have been developed for PCDD/F. By this approach the catalytic reactions are blocked by adding special inhibitors as poisoning compounds for copper and other metal species in the fly ash. Special aliphatic amines (triethylamine) and alkanolamines (triethanolamine) have been found to be very efficient as inhibitors for PCDD/F, and have been used in pilot plants. The effect can be seen in Figure 8.6. The inhibitors have been introduced into the incinerator by spraying them into the postcombustion zone of the incinerator at about... 

Table III collects and compares the rate date for the oxidation of some aliphatic amines and alcohols on nickel, silver, copper, and cobalt oxide anodes. Homologous alcohols always react 10 times slower than amines. The reaction rates on silver and on cobalt are sizeably slower than those on copper and nickel, so that silver and cobalt could be ruled out for technically applied anodic oxidation (190).

Lower aliphatic amines are widely used as intermediates for the synthesis of herbicides, insecticides and drugs or can be applied as rubber accelerators, corrosion inhibitors, surface active agents etc. [l]. The most widespread method for the preparation of lower aliphatic amines involves the reaction of ammonia with an alcohol or a carbonyl compound in the presence of hydrogen. The most common catalysts used for reductive amination of alcohols, aldehydes and ketones contain nickel, platinum, palladium or copper as active component [ I — 3 ]. One of the most important issues in the reductive amination is the selectivity control as the product distribution, i.e. the ratio of primary to secondary or tertiary amines, is strongly affected by thermodynamics. 

The most conspicuous property of aliphatic amines, apart from their fishy smell, is their high basicity, which usually precludes N-alkylations under acidic reaction conditions (last reaction, Scheme 6.3). Hence, alkylation of amines with tertiary alkyl groups is not usually possible without the use of highly stabilized carbocations which can be formed under basic reaction conditions. Rare exceptions are N-alkyla-tions of amines via radicals (Scheme 4.2), copper-catalyzed propargylations (Scheme 6.3), and the addition of amines to some Michael acceptors and allyl palladium or iridium complexes. Better strategies for the preparation of tert-alkylamines include the addition of Grignard reagents to ketone-derived imines [13] or the reduction of tert-alkyl nitro compounds. 

Compounds with a terminal acetylenic function, RCsCH, react with 1-bromoalkynes, R CsCBr in the presence of an aliphatic amine and a catalytic amount of a copper salt to give the coupling products RCsCCsCR. This useful reaction, discovered by Cadiot and Chodkiewicz [195], gives a ready access to a number of poly-unsaturated systems. The usual procedure involves dropwise addition of the bromoacetylene R GsCBr to a mixture of the acetylene RCsCH, ethylamine, ethanol or methanol, a catalytic amount of copper chloride or bromide and a small amount of hydroxylamine.HCl. This reducing agent prevents the oxidation to copper ). The reaction is usually very fast at temperatures in the region of 30 C. Since much heat is evolved, the reaction can be monitored easily by temperature observation. 

A ligandless and base-free Gu-catalyzed protocol for the coupling of arylboronic acids and potassium aryltrifluoro-borates with primary and secondary aliphatic amines and anilines was developed. The process utilized catalytic copper(n) acetate monohydrate or CuCl2 and 4 AMS in dichloromethane at slightly elevated temperatures under an atmosphere of oxygen (Equation (232)).1019-1021... 

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... 

For amination with aliphatic amines, copper catalysis is normally superior to palladium catalysis, e.g., <2006T4435>. Thus, reactions of primary or secondary amines, including pyrrolidine and morpholine, with 5-bromopyrimidine using copper bromide and a phosphite ligand give 5-aminopyrimidines in excellent yields (Scheme 116) <2006T4435, 2005OL3965>. 

The reactions catalyzed by laccases proceed by the monoelectronic oxidation of a suitable substrate molecule (phenols and aromatic or aliphatic amines) to the corresponding reactive radical (Riva, 2006). The redox process takes place with the assistance of a cluster of four copper atoms that form the catalytic core of the enzyme they also confer the typical blue color to these enzymes because of the intense electronic absorption of the Cu-Cu linkages (Piontek et al., 2002). The overall outcome of the catalytic cycle is the reduction of one molecule of oxygen to two molecules of water and the concomitant oxidation of four substrate molecules to produce four... 

There remains a variety of unstable, insoluble, or incompletely characterized complexes whose true formulas remain open to speculation. Many unstable 1 1 complexes between copper (I) halides and ammonia (31) or the lower aliphatic amines (71, 281, 336) have been studied manometrically, but the compounds formed have high dissociation pressures, and attempts to isolate them have been unsuccessful owing to loss of ligand or to oxidation. Complexes with higher amines (348) or with pyridine (334) and its oligomers (178, 229, 230) are, in... 

Acetylene and either primary or secondary aliphatic amines react under pressure at 80° to 100° in the presence of a copper catalyst to form N-mono- and N-di-substituted 3 aminobutynes, e.g., 3 [Pg.341]

In a related reaction, trifluoroarylboronates react with copper(II) acetate and then an aliphatic amine to give the A-phenylamine. ... 

Tlie cross-coupling of a terminal alkyne 9 with a 1 -bromoalkync 8 in the presence of an aliphatic amine and a catalytic amount of a Cu(I) salt affords unsymmetrically substituted diynes [10, Eq.(5)]. This useful reaction, discovered by Cadiot and Chodkiewicz [8], can be employed advantageously for the synthesis of several polyunsaturated systems. Generally the bromoalkyne is introduced dropwise to a mixture of the alkyne, ethylamine, and MeOH or EtOH in the presence of a catalytic amount of CuCl, and a small amount of NH OH-HCl. The reducing agent, NHjOH-HCl, is used to reduce the copper(TI) ion. The alkynylcopper(I) is assumed to be the reactive intermediate. The formation of the symmetrical diyne can be suppressed by maintaining the concentration of the bromoalkyne. This side reaction is particularly significant in the case of less acidic alkynes such as alkylalkynes [9J. 

Barton, D. H. R., Yadav-Bhatnagar, N., Finet, J. P., Khamsi, J. Phenylation of aromatic and aliphatic amines by phenyllead triacetate using copper catalysis. Tetrahedron Lett. 1987, 28, 3111-3114. 

Quach, T. D., Batey, R. A. Ligand- and Base-Free Copper(ll)-Catalyzed C-N Bond Formation Cross-Coupling Reactions of Organoboron Compounds with Aliphatic Amines and Anilines. Org. Lett. 2003, 5, 4397-4400. 

The heterocoupling of a terminal alkyne with a 1-bromoalkyne in the presence of an aliphatic amine and a catalytic amount of a copper(I) salt affords unsymmetrically substituted diynes (2 equation 5). This useful reaction, discovered by Chodkiewicz and Cadiot, can be employed advantageously for the synthesis of several polyunsaturated systems. 

Generally, reactions with anilines are slower than those with aliphatic amines, in part because anilines are less nucleophilic7. Condensation of aromatic amines with unactivated aryl halides usually requires the presence of copper catalysts. Reactions of diarylamines, such as diphenylamine and carbazole, are even slower. 

Copper-mediated reactions of arylboronic acids with aromatic and aliphatic amines... 

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. 

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