Formation Of Derivatives

• CARBOXYLIC ACID DERIVATIVES

  • CARBOXYLIC ACID
  • CARBOXYLATE
  • ESTER
  • AMIDE
  • THIOESTER
  • ACYL PHOSPHATE
  • ACYL CHLORIDE
  • ACID ANHYDRIDE
• DERIVATIVES

  • The important classes of organic compounds known as alcohols, phenols, ethers, amines and halides consist of alkyl and/or aryl groups bonded to hydroxyl, alkoxyl, amino and halo substituents respectively.
  • If these same functional groups are attached to an acyl group (RCO-) their properties are substantially changed, and they are designated as carboxylic acid derivatives.
  • Carboxylic acids have a hydroxyl group bonded to an acyl group, and their functional derivatives are prepared by replacement of the hydroxyl group with substituents, such as halo, alkoxyl, amino and acyloxy.
• Carboxylic acids

  • generally synthesized from alcohols and aldehydes.
  • Oxidative cleavage of alkenes also results in the formation of carboxylic acid
• Carboxylate

  • It is a negatively charged ion that is a conjugate base of a carboxylic acid, RCOO⁻. (This anion is formed when carboxylic acid dissociates.)
  • Water-soluble carboxylic acids ionize slightly in water to form moderately acidic solutions. (Their aqueous solutions exhibit the typical properties of acids, such as changing litmus from blue to red.)
• Ester

  • Fischer Reaction is the simplest method of formation of esters.
  • In this reaction an acid reacts with alcohol to form ester.
  • For example, ethanoic acid reacts with ethanol to form ethylethanoate.
• Amides

  • produced by the reaction of ammonia or amines with acid chlorides.
  • For instance, reaction of ammonia with propanoyl chloride will result in the formation of propanamide.
• Acid Anhydride

  • Acid chlorides react with carboxylic acids to form anhydrides
  • An organic acid anhydride is synthesized by the heating of two carboxylic acids at a high temperature of nearly 800℃.
  • In this process, one water molecule is removed from the reaction. It can be synthesized by the reaction of a carboxylic acid with P2O5.
• Thioesters

  • can be prepared by condensation of thiols and carboxylic acids in the presence of dehydrating agents.
  • A typical dehydration agent is DCC.
  • Efforts to improve the sustainability of thioester synthesis have also been reported utilising safer coupling reagent T3P and greener solvent cyclopentanone.
  • Acid anhydrides and some lactones also give thioesters upon treatment with thiols in the presence of a base.
• Thioesters

  • can be conveniently prepared from alcohols by the Mitsunobu reaction, using thioacetic acid.
  • They also arise via carbonylation of alkynes and alkenes in the presence of thiols.
• acyl phosphate

  • general term referring to an acyl group with a phosphate attached to the oxygen.
  • In many cases, enzymes activate a carboxylate group by converting it to an acyl phosphate, at the expense of an ATP.
  • It can also be formed by removing hydrogen from the oxygen of a carboxylic acid and replace it with phosphate
• Acyl Chloride (Replacing -OH by - Cl)

  • Converting RCOOH, into an acyl chloride, RCOCI.
  • Acyl chlorides are also known as acid chlorides.
  • The most commonly used example of the conversion of a carboxylic acid into an acyl chloride is ethanoic acid to ethanoyl chloride.
  • ethanoic acid to ethano yl chloride
  • Acyl chlorides are very reactive, and can be used to make a wide range of other things. That's why they are important.
• Acyl Chloride ( Replacing the -OH group using phosphorus(v) chloride, PCIs)

  • Phosphorus(V) chloride is a solid which reacts with carboxylic acids in the cold to give steamy acidic fumes of hydrogen chloride.
  • It leaves a liquid mixture of the acyl chloride and a phosphorus compound, phosphorus trichloride oxide (phosphorus oxychloride)
  • РОСІ3.
• Acyl Chloride (Replacing the -OH group using phosphorus(ill) chloride, PCI3)

  • Phosphorus(Ili) chloride is a liquid at room temperature.
  • Its reaction with a carboxylic acid is less dramatic than that of phosphorus (V) chloride because there is no hydrogen chloride produced.
• Acyl Chloride (Replacing the -OH group using thionyl chioride)

  • Sulfur dichloride oxide (thionyl chloride) is a liquid at room temperature and has the formula SOCI2.