ACID DERIVATIVES
Acid derivatives:- esters, -acid chlorides, -amides, -acid anhydrides
ESTERS
MF: C_nH_2nO₂
functional group: R-C(=O)OC-R
Formation of esters
-Esterification
reagent: alcohol + alkanoic acid
condition: conc H₂SO₄: catalyst + dehydrating agent , heat under reflux for several hours


-Alkanoylation/ Acylation of alcohol or phenol
reagent: alkanoyl/ acid chloride, R-C(=O)Cl
condition: room temp

observation: -fruity smell of ester, -steamy white HCl fumes

Physical properties
-lower members: volatile liquids w/ fruity smell, higher members: white, waxy solids
-only methymethanoate is soluble in water, other liquid ester only soluble in non-polar organic solvents (ethylethanoate: good solvent in lacquer & glue)

Hydrolysis
-Acid Hydrolysis
reagent: dil HCl
condition: heat under reflux
R-C(=O)-C-R + H₂O >(dil HCl, heat, reflux)> R-C(=O)-OH + R-C-OH
-Alkaline Hydrolysis
reagent: NaOH(aq)
condition: heat under reflux
R-C(=O)-C-R + NaOH + H₂O >(heat, reflux)> R-C(=O)-O^-Na⁺ + R-C-OH + H₂O

volatile liquid esters: pleasant fruity smell
flavour & smells in fruit & flowers = mixture of org cpds, esters
esters: in artificial flavouring and perfumery

Esters in nature
-waxes: esters of long C chained acid & alcohol
-fats & oils (lipids): at rtp; fats- (s), oils-(l)
fats & oils: triglycerides = esters of propane-1, 2, 3-triol (glycerol) & long-chain carboxylic acid
-pheromones: cpds in animals to communicate

ACID CHLORIDES
MF: R-C(=O)-Cl (alkanoyl chloride / acyl chloride)
-used to introduce alkanoyl group, R-C(=O) into cpds through alkanoylation / acylation
Physical properties
-ethanoyl & benzoyl chloride: (l) at rtp, sharp, characteristic smell and cause fumes in moist air (HCl gas formed)

Formation
reagent: PCl₅ + carboxylic acid
condition: room temp
R-C(=O)-OH + PCl₅ > R-C(=O)Cl + POCl₃ + HCl

Hydrolysis
reagent: water
condtion: room temp

observation: steamy white fumes of HCl gas

Acid chloride, CH3C(=O)Cl	Halogenoalkane, CH3CH2Cl	Halogenobenzene, C6H5Cl
most reactive CH3C(=O)Cl + H2O >(room temp)> CH3C(=O)OH + HCl	no reaction w/ water but w/ dil NaOH when boiling under reflux CH3CH2Cl + NaOH >(heat, reflux)> CH3CH2OH + NaCl	least reactive: no reaction w/ water, but only w/ conc NaOH heated under pressure C6H5Cl + conc NaOH >(heat under pressure)> C6H5O-Na+ + NaCl + H2O
electronegative Cl atom & O atom pull e-s away from carbonyl C atom > C atom more +ve > more susceptible to nucleophilc substitution	polar C-Cl bond > C atom a bit +ve > susceptible to nucleophilic substitution	delocalistaion of Cl e- into benzene ring > C-Cl bond not very polar anymore > not very susceptible to nucleophilic substitution

Reaction w/ ammonia to form amine
reagent: ammonia
condition: room temp


Reaction w/ amine to form substituted amide
reagent: amine, R-NH₂
condition: room temp

[R-C(=O)-O-C-R': N-alkylalkanamide, alkyl: R', alkan: R]

Ester formation
-w/ alcohols
reagent: alcohol
condition: room temp


-w/ phenol
reagent: phenol
condition: room temp
R-C(=O)-Cl + H-O-C₆H₅ > R-C(=O)-C₆H₅ + HCl
[acid anhydrides: also alkanoylating agent to introduce alkanoyl group into other cpds, reation same as alkanoyl chlorides but instead of HCl formed, carboxylic acid is formed]
ethanoic anhydride,

Ethanoic anhydride + alcohol:

Ethanoic anhydride + amine:


AMIDES
MF: C_nH_2n+1-C(=O)NH₂
functional group: amide group, -C(=O)NH₂
substituted amides: H atom of amide replaced by alkyl or phenyl group R
-C(=O)NH-R (N-alkylalkamide) [C₆H₅ C(=O)NHCH₃: N-methylbenzamide]

Formation
reagent: ammonia, acid chloride
condition: room temp


[for substituted amides: reagent: alkylamine, acid chloride]
condition: room temp


Physical properties
-methanamide: gas at rtp, other amides: white, crystalline solids (strong intermolecular H-bonds)
-higher than expected mp + bp (electronegative O atom in amide > polar molecule > strong H-bonds)
-lower members soluble in water (benzamide: soluble in hot water)

Hydrolysis
-Acid hydrolysis
reagent: dil HCl (or dil mineral acid)
condition: heat under reflux
R-C(=O)NH₂ + H₂O + HCl >(heat, reflux)> R-C(=O)OH + NH₄Cl
-Alkaline hydrolysis
reagent: NaOH (aq)
condition: heat under reflux
R-C(=O)NH₂ + NaOH >(heat, reflux)> R-C(=O)O^-Na⁺ + NH₃

Reduction
reagent: lithium hydriodoaluminate (III), LiAlH₄ in dry ether
condition: ice-cold temp (<10°C)
R-C(=O)NH₂ + 4[H] >(LiAlH₄, <10°C)> R-CH₂NH₂ + H₂O

[LiAlH₄ & sodium borohydride, NaBH₄: reduces -C(=O)- to -CH(OH)-
hydrogen gas & nickel catalyst: reduces -C=C- to -CHCH-, -CN to -CH₂NH₂-]

ALKANONITRILE
MF: C_nH_2n+1CN
functional group: cyano group,

Formation
reagent: halogenoalkane + aq, ethanolic KCN
condition: heat under reflux
R-X + KCN (aq. ethanolic) >(heat under reflux)> R-CN + KX
(nucleophilic substitution: CN^- replaces X)

Hydrolysis to alkanoic acid
-Acid hydrolysis
reagent: dil HCl
condition: heat under reflux
R-CN + HCl + 2H₂O >(heat, reflux)> R-C(=O)OH + NH₄Cl
-Alkaline hydrolysis
reagent: NaOH (aq)
condition: heat under reflux
R-CN + NaOH + H₂O >(heat, reflux)> R-C(=O)O^-Na⁺ + NH₃

Reduction
reagent: H₂ gas + Ni catalyst
condition: heat under slight pressure
R-CN + 2H₂ >(H₂/Ni, pressure)> R-CH₂NH₂


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