Acetamide metal complexes

Table 1 Hsts many of acetamide s important physical properties. Acetamide, CH2CONH2, dissolves easily ia water, exhibiting amphoteric behavior. It is slow to hydroly2e unless an acid or base is present. The autodissociation constant is about 3.2 x 10 at 94°C. It combines with acids, eg, HBr, HCl, HNO, to form soHd complexes. The chemistry of metal salts ia acetamide melts has been researched with a view to developing electroplating methods. The hterature of acetamide melts and complexes, their electrochemistry and spectroscopy, has been critically reviewed (9).

Hydration of nitriles providing carboxamides is usually carried out m strongly basic or acidic aqueous media - these reactions require rather bars conditions and suffer from incomplete selectivity to the desired amide product. A few papers in the literature deal with the possibihty of transition metal catalysis of this reaction [28-30]. According to a recent report [30], acetonitrile can be hydrated into acetamide with water-soluble rhodium(I) complexes (such as the one obtained from [ RhCl(COD) 2] and TPPTS) under reasonably mild conditions with unprecedently high rate... 

The molecules producing coordinative saturation need not be chelating. As a by-product to the study of synergism in the extraction of alkali metal chelate salts, Healy (14) isolated crystalline complexes Li(PhCO-CHCOPhJSa where S = tri-n-octylphosphine oxide or N, N-dibutyl-acetamide. 

The lactams 2-pyrrolidinone and lV-methyl-2-pyrrolidinone may be used to increase the solubility of carbohydrates in alcoholic reaction media. However, they cannot be used in the preparation of metal halide adducts, because of their tendency to associate, perhaps by complexing, with metal halide adducts.1 Amides are known to form complexes with metal halides. For example, sodium iodide combines with N, N-dimethylformamide to give Nal 3 N,N-dimethylformamide. Acetamide can form NaBr 2 acetamide and NaI-2 acetamide. 7... 

The carboxylic acid amides most conunonly studied as ligands are formamide, acetamide, and the W-substituted derivatives, particularly A,A-dimethylformamide (DMF). These compounds are often used as solvents and have high dielectric constants, particularly when they contain an N-H bond, and such uses helped to stimulate interest in the amides as ligands. There are two possible donor atoms, N or O, but all complexes of the simple amide ligands, characterized by X-ray structure determination at least, have M-O bonds. The amides are usually terminal ligands but can bridge between metal atoms in some instances. 

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