Amides copper bromide

COPPER BROMIDE (7789-45-9) BFjCu Aqueous solution is an acid. Incompatible with bases, inducing amines, amides, and inorganic hydroxides strong oxidizers, including chlorine, fluorine, peroxides and hydroperoxides potassium. 

It has been found that a number of bidentate ligands greatly expand the scope of copper catalysis. Copper(I) iodide used in conjunction with a chelating diamine is a good catalyst for amidation of aryl bromides. Of several diamines that were examined, rra s-yV,yV -dimethylcyclohexane-l,2-diamine was among the best. These conditions are applicable to aryl bromides and iodides with either ERG or EWG substituents, as well as to relatively hindered halides. The nucleophiles that are reactive under these conditions include acyclic and cyclic amides.149... 

Some other examples of metal-catalyzed substitutions are given in Scheme 11.10. Entries 1 to 3 are copper-catalyzed reactions. Entry 1 is an example of arylation of imidazole. Both dibenzylideneacetone and 1,10-phenanthroline were included as ligands and Cs2C03 was used as the base. Entry 2 is an example of amination by a primary amine. The ligand used in this case was (V,(V-diethyl sal icyl amide. These conditions proved effective for a variety of primary amines and aryl bromides with both ERG and EWG substituents. Entry 3 is an example of more classical conditions. The target structure is a phosphodiesterase inhibitor of a type used in treatment of asthma. Copper powder was used as the catalyst. 

In recent years, cross-coupling methodology has emerged as a viable tool for enamide synthesis, and, indeed, there are a number of published protocols which employ palladium- or copper-catalyzed stereospecific amidations of vinyl halides [17]. For example, Buchwald and coworkers had recently shown that a copper-catalyzed cross-coupling of vinyl bromides or iodides proceeded with retention of stereochemistry (Scheme 9.16), though the only example using a tetrasubstituted vinyl halide, 23, lacked the need for any stereochemical control in the halide portion [18]. Based on this it seemed feasible that the desired enamide 22 could potentially be assembled via a comparable coupling between amide 24 and a stere-odefined vinyl halide such as 25. 

In the carbonylation reactions, further reaction of the acyl lithium compounds with carbon monoxide can occur, but clean reaction can be achieved if the lithium amide is first converted to a copper derivative (Scheme 130) (79JOC3734). In the case of morpholine, reaction with allyl bromide gave a 93% overall yield of the amide product. 

The initial synthetic approach to conivaptan HCl (1) employed by the Yamanouchi discovery group26 commenced with commercially available benzazepinone 10. Acylation of 10 with p-nitrobenzoyl chloride provided benzamide 11. Subsequent hydrogenation of 11 over palladium on carbon yielded aniline 12, which was in turn condensed with biphenyl-2-carbonyl chloride to provide bis(amide) 13. Bis(amide) 13 was subsequently heated with copper(II) bromide in boiling chloroform/ethyl acetate to furnish a-bromoketone 14. It is interesting that condensation of a-bromoketone 14 with acetamidine hydrochloride in the presence of potassium carbonate in boiling acetonitrile afforded not only the desired imidazobenzazepine product (1 53% yield, 2 steps) but also the related oxazolobenzazepine 15 (7% yield, 2 steps), which presumably resulted from nucleophilic attack of the benzazepinone oxygen on the amidine moiety followed by loss of ammonia. Separation of oxazolobenzazepine byproduct 15 from imidazobenzazepine 1 by silica gel chromatography followed by treatment of the purified imidazobenzazepine free-base with hydrochloric acid then provided conivaptan HCl (1). 

Copper(n)-catalyzed intramolecular amidation of alkynyl bromide 217 led to macrocyclic ynamide 218 in 76% yield (Equation 21) <2006JOC4170>. 

Copper(II) bromide is another reagent that has been used successfully for the dehydrogenation of ketones and amides (equation 21). This procedure, which presumably proceeds via the a-bromo compounds, (c/. Section 2.2.2) was found to have particular advantages over a number of alternative methods for the dehydrogenation of some dihydrouracils. ... 

Dehydrohalogenation of amide chlorides affords a-chloroenamines, which undergo cycloaddition with IV-diphenylmethylaldimines to furnish azetidinium salts (303 equation 161). From these salts the diphe-nylmethyl group can be removed by hydrogenation, subsequent deprotonation yields 2-amino-1-aze-tines. The addition of primary or secondary amines to nitrilium salts gives rise to formation of amidinium salts and amidines respectively, e.g. (304 equation 162). In a similar reaction from copper(I) imidazolide, r-butyl bromide and nitriles amidines (305 equation 163) were prepared. ... 

Novel imidazolidinone tetrahydropyrroloindole. During the attempted total synthesis of roquefortine C, a fungal metabolite of Penicillium roqueforti, an essential fungus in the production of Roquefort cheese, the copper catalyzed amidation of the vinyl bromide 34 in Scheme 1 was envisioned to lead to the requisite diketopiperazine ring contained in 35. " Preliminary spectroscopic data, however, suggested that the amidation had not gone as anticipated and that an unknown cyclization product had instead formed. 

When saturated alkyl halides were used in place of allyl compounds, a zinc/cop-per couple or zinc dust/copper iodide promoted the 1,4-addition to a-enones or a-enals. Sonication enhanced the efficiency of the process leading to the 1,4-adducts in very good yields [166]. This reaction was later extended to various a,j3-unsaturated compounds such as esters, amides and nitriles [167]. The reactivity of the halide followed the order tertiary > secondary primary and iodide > bromide > chloride making the assumption of a radical process highly probable [168]. 

Tetrazoles are usually prepared by the reaction of an azide with a nitrile, or an activated amide tri-n-bntyltin azide and trimethylsilyl azide are more convenient and safer reagents than azide anion in some cases copper(I) oxide catalysis in the trimethylsilyl azide protocol is very efficient for the prodnction of A-unsubstituted tetrazoles, " and arylsulfonyl cyanides react with organic azides very efficiently giving rise to 1-substitnted 5-arylsulfonyl-tetrazoles. Zinc bromide can be used to catalyse the reaction between sodinm azide and nitriles in hot water. Intramolecnlar examples involving cyanamides proceed in hot DMF. 3 In additions to nitriles, one can inclnde triethylammoninm chloride (instead of ammoninm chloride)... 

MERCURIC BROMIDE (7789-47-1) HgBfj Noncombustible solid. Light and heat cause decomposition keep out of sunlight. Violent reaction with strong oxidizers, including chlorine trifluoride. Aqueous solution is acidic. Incompatible with acetylene, ammonia, azides (may form mercury azide, a heat- and shock-sensitive explosive), bases, caustics, amines, amides, inorganic hydroxides calcium (forms amalgam) carbide, chlorine dioxide, copper and its alloys hydrazines, indium (violent at 662°F/350°C), lithiiun, potassium, rabidium, sodium. Note Be especially careful not to allow this compound to accumulate in sink traps with many of the above incompatible... 

In addition to the desired product, route C produces hydrogen, sodium chloride and additional ammonia (from quenching of the sodium amide with ammonium chloride), zinc and copper hydroxides from the reduction (for simplicity we will assume one mole of each, and no other by-products), one third of a mole of phosphorous acid, sodium bromide, ethanol (from the ester hydrolysis) and carbon dioxide (from the decarboxylation). The molecular weights involved are therefore 126, 1,... 

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