Metal carboxylates carboxylic acids

If the starting material contains M-H or M-C bonds a further complication can arise due to the possibility of a CO2 insertion reaction. Thus, both [Ru(H)2(N2)(PPh3)3] and [Ru(H)2(PPh3)4] react to give the formate [Ru(H)(OOCH)(PPh3)3], and similar CO2 insertions into M-H are known for M = Co, Fe, Os, Ir, Pt. These normal insertion reactions are consistent with the expected bond polarities M +-H and 0 =C +=0, but occasionally abnormal insertion occurs to give metal carboxylic acids... 

Though only an alkyl complex is possible in the ethylene insertion, there are several possible products of the C02 insertion, such as p -OCOH, p2-02CH, and p -COOH species, as shown in Figure 4. Thus, the following issues were investigated for the C02 insertion reactions (1) Which species is more easily formed, the metal-formate (M-OCOH) or the metal-carboxylic acid (M-COOH) (2) What are the most important interactions in the C02 insertion (3) How different is the C02 insertion from the C2H4 insertion ... 

See also the reaction of epoxides with alpha metallated carboxylic acids and derivatives on page 1717, Section 5. 

Chapter 28. Synthetic Applications of Metalated Carboxylic Acids P. L. Creger, Parke, Davis Co., Ann Arbor, HI 8106... 

IV. Reactions of Metalated Carboxylic Acids - Metalated carboxylic acids react with most electrophiles It the dianlon is associated with alkali metal cations. However, Cu(i) dianions22 react readily only with activated allylic or benzylic halides. 

A. Alkylation 1. Alkyl Halides - Alkylation is, perhaps, the most useful syntheticreaction of metalated carboxylic acids. The reaction proceeds smoothly and it produces preparative yields of products for a variety of functionally different alkyl halides, including examples susceptible to elimination.10 The reaction is not sensitive to the leaving group, nor is it sensitive to steric effects as the following examples12 L4, 16 illustrate. The Haller-Bauer procedure fails where two of... 

Epoxides - The first indication of the synthetic utility of metalated carboxylic acids resulted from efforts to prepare steroidal aldosterone inhibitors from spiroepoxides.39 Model studies indicated that the reaction fails as a result of severe steric hindrance in either the epoxide or carboxylic acid and that monosubstitution occurs for the same reason.39 The reaction has been used in a key step of an elegant synthesis of vernolepin, 5. 40 Forcing conditions are required, and, in contrast to acid dianions, anions of unactivated esters fail to react with epoxides.39 41... 

B. Addition to Carbonyl Compounds - Addition of metalated carboxylic acids to aldehydes and ketones affords a useful and versatile alternative to the Reformatsky reaction.42 The reaction is sensitive to steric effects... 

Esters react with metalated carboxylic acids yielding P-ketoacids from which aldehydes50 and ketones51 may be derived. Like the Adam olefin... 

Carbon dioxide was the first electrophile demonstrated to react with metalated carboxylic acids.9 The reaction has been used to measure the extent of metalation23 and to prepare malonie acids which would be difficult to obtain by other methods.52 Malonie acid esters are available... 

C. Oxygenation - Metalated carboxylic acids react instantaneously with oxygen, and, depending upon reaction and workup conditions, C -hydroxy-56 or a-hydroperoxycarboxylic acids57 are obtained. If low temperatures... 

Although the solid state reactivity of one class of metal-carboxylic acid complexes--those of acrylic acid and methacryllc acid--has been known for some time ( ), little convincing Information exists as to whether the structural basis for reactivity can be... 

Saponification The alkaline hydrolysis of an ester into an alcohol and alkali metals carboxylic acid salt. 

BUTOXYETHYL ACETATE or BUTOXYETHYL CELLOSOLVE ACETATE [Union Carbide] (112-07-2) CsH.,03 Combustible liquid. Forms explosive mixture with air [explosion limits in air (vol %) 0.9 to 8.5 flash point 160°F/71°C autoignition temp 645°F/341°C Fire Rating 2]. Violent reaction on contact with strong oxidizers. Incompatible with alkali metals carboxylic acids epoxides such as glycidol, isocyanates, permanganates, peroxides and hydroperoxides, ammonium persulfate ... 

Creger PL. Metalated carboxylic acids. U. Monoalkylation of metalated toluic adds and dimethylbenzoic acids. J. Am. Chem. Soc. 1970 92 1396 1397. 

An improved method [16] of preparation of the a-hydroperoxy carboxylic acid is the singlet oxygenation of a-metalated carboxylic acids. 

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