Organometallic compounds with carboxylic acids

The interaction of organometallic compounds with carboxylic acid chlorides and /V,/V-dimethylcarboxamides (Expt 5.94). 

THE INTERACTION OF ORGANOMETALLIC COMPOUNDS WITH CARBOXYLIC ACID CHLORIDES AND A DIMETHYLCARBOXAMIDES... 

Fig. 6.47. Top three reactions chemoselective acylations of weakly nucleophilic organometallic compounds with carboxylic acid chlorides.

Many metals occur in crude oils. Some of the more abundant are sodium, calcium, magnesium, aluminium, iron, vanadium, and nickel. They are present either as inorganic salts, such as sodium and magnesium chlorides, or in the form of organometallic compounds, such as those of nickel and vanadium (as in porphyrins). Calcium and magnesium can form salts or soaps with carboxylic acids. These compounds act as emulsifiers, and their presence is undesirable. 

Acylation is one of the most fundamental and useful reactions in organic synthesis and is normally achieved by the reaction either with carboxylic acid derivatives and organometallic compounds or with masked acyl anions and aUcyl halides. 

Carboxylic acid groups can also be installed in molecules using the reaction of an organometallic compound with carbon dioxide. This is a reductive method since the carbon dioxide is reduced to a carboxylic acid by formation of a new carbon-carbon bond. Both Grignard reagents and organolithium compounds work well in this reaction. 

Many hydride donors, organometallic compounds, and heteroatom-stabilized carbanions react with carboxylic acids and their derivatives. However, the corresponding substitution... 

Acylation of Organometallic Compounds and Heteroatom-Stabilized Carbanions With Carboxylic Acid (Derivative)s Synthesis of Ketones... 

Reaction of organometallics bearing an a-seleno carbanion with carboxylic acid derivatives and related compounds... 

Aldehydes 62 were reacted vdth an excess of either n-butyllilhiurn or allylmagne-sium chloride 63 to give the metal alkoxides 64, which were quenched with carboxylic acid functionalized resin. This resin also served a dual role in quenching the excess organometallic reactant The excess carbonyl compound was quenched with a primary amine substituted resin and the products were obtained > 95 %... 

The most general synthetic route to ketones uses the reaction of carboxylic acids (or their derivatives) or nitriles with organometallic compounds (M.J. Jorgenson, 1970). Lithium car-boxylates react with organolithium compounds to give stable gem-diolates, which are decom-... 

Nitriles are similar in some respects to carboxylic acids and are prepared either by SN2 reaction of an alkyl halide with cyanide ion or by dehydration of an amide. Nitriles undergo nucleophilic addition to the polar C=N bond in the same way that carbonyl compounds do. The most important reactions of nitriles are their hydrolysis to carboxylic acids, reduction to primary amines, and reaction with organometallic reagents to yield ketones. 

The Conversion of Carboxylic Acid Salts to Ketones With Organometallic Compounds... 

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