Amines reactions with organometallics

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 electrophilic amination reaction of organometallic species using mono-, di- and trihaloamines has attracted a lot of attention for the synthesis of amines. Only a few cases have been reported using alkylchloroamines as precursors for the synthesis of tertiary amines One example is the reaction of functionalized aryhnagnesium compounds with benzyl-V-chloroamines 252 providing polyfunctional tertiary amines 253 (equation 164) °. The procedure was also applied for the preparation of chiral V-chloro-amines with retention of chirahty at the a-carbon. However, the amination process is limited to benzyl-V-chloroamines. 

SCHEME 12. Potential mechanisms for copper-catalyzed amination reactions with low-valent organometallic reagents... 

Polar solvents such as ethers and amines react with organometallic initiators, as well as propagating polystyryl and polydienyl carbanions, to decrease the concentration of active centers [3, 44, 45]. The rate of reaction with ethers decreases in the order Li > Na > K. For example, dilute solutions of poly(styryl)lithium in THF at room temperature decompose at the rate of a few percent each minute. Alkyllithium initiators also react relatively rapidly with ethers the order of reactivity of organolithium compounds with ethers is tertiary RLi > secondary RLi > primary RLi... 

Related amination reactions of organometallic compounds RM have been performed with )V,)V dimethyl-0-(mesityl-sulfonyl)hydroxylamine (20), )V,)V-dimethyl-0-(phenylsul-fonyl)hydroxylamine (21), and )V,)V-dimethyl-O-(j0-tolylsul-fonyl)hydroxylamine (22). Stmctures (23)-(26) provide exanples of A(jV-dimethylamines formed by reactions of RM with the mesitylsulfonyl species (20). ... 

Acidity of Amides, Imides, and Sulfonamides Characteristic Reactions Reaction with Water Hydrolysis Reaction with Alcohols Reactions with Ammonia and Amines Reaction of Acid Chiorides with Salts of Carboxylic Acids Interconversion of Functional Derivatives Reactions with Organometallic Compounds 18.10 Reduction... 

Diphenylphosphinic mixed anhydrides have been utilized to form peptide bonds. Peptides are easier to isolate by this method than by employing 1,3-Dicyclohexylcarbodiimide. These anhydrides are the method of choice for the formation of amides of 2-alkenoic acids (eq 1 ). Carbodiimide and acyl carbonate methods proved to be inferior. Primary amines result in better yields than secondary amines. This activation protocol can be employed to form thiol esters (eq 2) p-Amino acids are readily converted to p-lactams with chlorodiphenylphosphine oxide (eq 3). Secondary amines work best. This activation protocol has been utilized to convert acids to amines via a Curtius rearrangement. Phenols have been generated from diene acids, presumably via base-induced elimination of diphenylphosphinic acid from the mixed anhydrides to form ketenes which spontaneously cyclize. Acids have been converted to ketones via activation followed by reaction with organometallic reagents (eq 4)."... 

Zirconium tetrachloride is instantly hydrolyzed in water to zirconium oxide dichloride octahydrate [13520-92-8]. Zirconium tetrachloride exchanges chlorine for 0x0 bonds in the reaction with hydroxylic ligands, forming alkoxides from alcohols (see Alkoxides, METAl). Zirconium tetrachloride combines with many Lewis bases such as dimethyl sulfoxide, phosphoms oxychloride and amines including ammonia, ethers, and ketones. The zirconium organometalLic compounds ate all derived from zirconium tetrachloride. 

The reaction of organometalic compounds with nitrones can be applied not only to the synthesis of stable nitroxyl radicals but also to the preparation of optically active secondary amines (Scheme 2.162) (617, 618). 

The action of chloroamine and bromoamine on organometallic reagents has been reviewed102 and a comprehensive review of electrophilic aminations of carbanions has appeared103. Alkyl, alkenyl and aryllithium compounds are converted into tertiary amines 84 by reaction with the mesityl compounds 83 (R2 = Me or Et Ar = 2,4, 6-MesCeHj)104. 

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