Organometallic hydrolysis

If r[, the rate of reaction 1, is extremely high, then the secondary reaction of the substrate E with the hydrocarbon organometallic does not take place The temperature at which the reaction mixture is subsequently terminated by hydrolysis IS also an important factor... 

Hydrolysis of Pb" salts leads to different structures, p. 395.) It seems unlikely that pure Sn(OH)2 itself has ever been prepared from aqueous solutions but it can be obtained as a white, amorphous solid by an anhydrous organometallic method ... 

The Hoch-Campbell aziridine synthesis entails treatment of ketoximes with excess Grignard reagents and subsequent hydrolysis of the organometallic complex. ... 

The Peterson olefination is a quite modern method in organic synthesis its mechanism is still not completely understood. " The a-silyl organometallic reagent 2 reacts with the carbonyl substrate 1 by formation of a carbon-carbon single bond to give the diastereomeric alkoxides 4a and 4b upon hydrolysis the latter are converted into /3-hydroxysilanes 5a and 5b ... 

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 most common reactions of carboxylic acid derivatives are substitution by water (hydrolysis) to yield an acid, by an alcohol (alcoholysis) to yield an ester, by an amine (aminolysis) to yield an amide, by hydride ion to yield an alcohol (reduction), and by an organometallic reagent to yield an alcohol (Grignard reaction). 

The reaction of 3-benzoxepin with methyllithium results in the addition of two equivalents of the organometallic reagent and cleavage of the heterocycle. After hydrolysis l-[2-(Z)-prop-l-enyl)phenyl]propan-2-ol can be isolated, but no experimental data is available.216 Occasionally, a small amount of the tran.v-isomcr is obtained (less than 10% of the product).12... 

Arylalkylamines 6 by Addition of Organometallic Reagents to 1,3-Oxazolidines 4 and Oxidative Cleavage and Hydrolysis General Procedure22 ... 

The carboxylic acids of organometallic systems are important synthetic intermediates that have been prepared by many different synthetic methods. Perrocenecarboxylic acid has been studied the most extensively,7 and the best laboratory syntheses previously reported involve hydrolysis of cyanoferrocene [Ferrocene, cyano-]8 or of /S-methylferrocenethiocarbonate [Ferrocene, [(methylthio)thioxo-methyl]-].9... 

Arylboronic acids have traditionally been prepared via the addition of an organomagnesium or organolithium intermediate to a trialkyl borate. Subsequent acidic hydrolysis produces the free arylboronic acid. This limits the type of arylboronic acids one can access via this method, as many functional groups are not compatible with the conditions necessary to generate the required organometallic species, or these species may not be stable intermediates. 

An interesting example for the preparation of functional disiloxanes by use of organometallic techniques is the synthesis of l,3-bis(4-hydroxybutyl)t.etramethyl-disiloxane as shown in React ion Scheme VI. The first, part of the reaction is conducted at the reflux temperature of tetrahydrofuran (THF) and methyl iodide is used as catalyst. The ratio of dichlorodimethylsilane to magnesium and to THF affects the yield of the cyclic product very strongly. The disiloxane is obtained in about 70% yield by aqueous hydrolysis of the purified cyclic intermediate under mild conditions and in the presence of a small amount of hydrochloric acid. 

Formation constants for complex species of mono-, di-, and trialkytin(rV) cations with some nucleotide-5 -monophosphates (AMP, LIMP, IMP, and GMP) are reported by De Stefano et al. The investigation was performed in the light of speciation of organometallic compounds in natural fluids (I = 0.16-1 moldm ). As expected, owing to the strong tendency of organotin(IV) cations to hydrolysis (as already was pointed above) in aqueous solution, the main species formed in the pH-range of interest of natural fluids are the hydrolytic ones. ... 

Organometallic compounds can be hydrolyzed by acid treatment. For active metals such as Mg, Li, and so on, water is sufficiently acidic. The most important example of this reaction is hydrolysis of Grignard reagents, but M may be many other metals or metalloids. Examples are SiRs, HgR, Na, and B(OH)2- Since aryl Grignard and aryllithium compounds are fairly easy to prepare, they are often used to prepare salts of weak acids, for example,... 

Part of this symposium was directed to the synthesis, properties and applications of inorganic and organometallic macromolecules with network structures. The section on organo-oxo macromolecules relevant to sol-gel processing addresses the interesting synthesis and challenging characterization efforts in this area. Brinker (p. 314) outlines the complex chemical and physical factors which affect network formation and structure resulting from the hydrolysis of a tetraalkoxysilane. 

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