Carboxylic acids nitriles

Under a pressure of 4,5 ml the 1 methyl-4-phenyl-piperidine-4-carboxylic acid nitrile passes over at a temperature of about 148°C in the form of a colorless oil under a pressure of 6 ml it passes over at about 158°C. After having been allowed to cool the distillate solidifies completely to form a crystalline mass. Its solidification point is at 53°C the yield amounts to about 135 parts, that is, about % of the theoretical yield. When recrystallized from isopropyl alcohol the hydrochloride of the nitrile forms colorless crystals, readily soluble in water and melting at 221° to 222°C. 

Carboxylic -acids, nitriles, aldehydes, ketones Steam - distillation, solvent extraction, ion exchange chromatography, GC [677]... 

In the following sections, we consider additional syntheses of ketones and aldehydes that we have not covered before. These syntheses form ketones and aldehydes from carboxylic acids, nitriles, acid chlorides, and alkyl halides. 

Although nitriles lack an acyl group, they are considered acid derivatives because they hydrolyze to carboxylic acids. Nitriles are frequently made from carboxylic acids (with the same number of carbons) by conversion to primary amides followed by dehydration. They are also made from primary alkyl halides and tosylates (adding one carbon) by nucleophilic substitution with cyanide ion. Aryl cyanides can be made by the Sandmeyer reaction of an aryldiazonium salt with cuprous cyanide. a-Hydroxynitriles (cyanohydrins) are made by the reaction of ketones and aldehydes with HCN. 

Chlorobis(cyclopentadienyl)tetnihydrobor8tozirconiuni(IV), Cp2Zr(CI)BH4. Mol. wt. 271.70. An early preparation has been reported without details. A convenient preparation involves reaction of Cp2Zr(H)Cl and BHi-S(CHj)2 yield 70-80%. Reduction of carbonyl groups Aldehydes and ketones are reduced by this complex in high yield esters, carboxylic acids, nitriles, and nitro compounds are reduced very slowly. The reagent thus resembles NaBH4, but can be used for reductions in benzene. 

Non-isohypsic transformations are especially important in the syntheses of various nitrogen-containing derivatives. A common route for obtaining amines is the reduction of nitrogen-containing derivatives of carboxylic acids (nitriles or amides), aldehydes and ketones (imines) ... 

Sodium borohydride reduction offers a significant advantage in synthetic applications. The method allows the reductive removal of halides selectively without affecting other functional groups, such as ester, carboxylic acid, nitrile and sulfone. A typical chemoselective dehalogenation is illustrated in Scheme 19. ... 

Intramolecular cyclization occurs with carboxylic acid nitriles, amide nitriles, and ester amides under strongly basic and anhydrous conditions. 

Esters Carboxylic acids Nitriles Ketones Amides Esters Nitriles Acyl chlorides Acid anhydrides Acyl cyanides Carbon dioxide Alkyl dialkoxyphosphinyl formate A l imidazoles Thiol esters Thio esters... 

Similar to LiAlH4. Good for carboxylic acids. Nitriles can be converted to aldehydes and aromatic aldehydes to aromatic methyl. 

Acceptors, a, P-Unsaturated ketones Esters Aldehydes, Amides Carboxylic acids Nitriles Sulphoxides Phosphonates and Phosphoranes. 

When particular functions such as thiol, alcohol, carboxylic acid, nitrile or silyl derivatives, are present at one end of the bolas, they can easily stack on solid surfaces like gold, silver, copper or silica and form planar molecular monolayer (coated particles) (Fig. 7.33). The hydrophobic core may serve as a barrier or a solvent and the available headgroup allows molecular recognition in solution. 

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