Post on 24-Dec-2015
THEME: Structure and chemical THEME: Structure and chemical properties of carboxylic acids. properties of carboxylic acids. Heterofunctional compounds.Heterofunctional compounds.
LECTURELECTURE 22
LecturerLecturer: Yevheniya. B. DmukhalskaYevheniya. B. Dmukhalska
PlanPlan1. Nomenclature of carboxylic acids2. Physical properties of carboxylic acids.3. Classification of carboxylic acids4. Methods of preparation of carboxylic acids5. Chemical properties of carboxylic acids.6. Heterofunctional compounds. 7. Hydroxy-acids, nomenclature, isomerism,
chemical properties and specific reactions for hydroxy-acids.
8. Introduction of optical isomerous. Mirror (optical) isomerism. Asymmetric carbon atom. Properties of enantiomers.
Carboxylic acids Carboxylic acids Carboxylic acids Carboxylic acids are compounds whose are compounds whose characteristic functional group is the carboxyl characteristic functional group is the carboxyl group group -- COOH COOH , example: , example:
Common formula of carboxylic acid: Common formula of carboxylic acid:
Formula Common Name IUPAC Name
HCO2H formic acid methanoic acid
CH3CO2H acetic acid ethanoic acid
CH3CH2CO2H propionic acid propanoic acid
CH3(CH2)2CO2H butyric acid butanoic acid
CH3(CH2)3CO2H valeric acid pentanoic acid
CH3(CH2)4CO2H caproic acid hexanoic acid
CH3(CH2)5CO2H enanthic acid heptanoic acid
CH3(CH2)6CO2H caprylic acid octanoic acid
CH3(CH2)7CO2H pelargonic acid nonanoic acid
CH3(CH2)8CO2H capric acid decanoic acid
Nomenclature of carboxylic acidsNomenclature of carboxylic acids
Classification of carboxylic acids : Classification of carboxylic acids :
1. By the nature of hydrocarbon radical1. By the nature of hydrocarbon radicala) a) saturated acids;saturated acids;
b) b) unsaturated acids unsaturated acids
c) c) aromatic acidaromatic acid
2. By 2. By the number of carboxyl groupsthe number of carboxyl groupsa) monocarboxylic acids;a) monocarboxylic acids;
b) dicarboxylic acids.b) dicarboxylic acids.
Saturated acidsSaturated acidsare acids, which have only simple bonds in are acids, which have only simple bonds in molecule. Example: molecule. Example:
methanoic (formic) acidmethanoic (formic) acid
ethanoic (acetic) acidethanoic (acetic) acid
propanoic (propanoic (propionic acid) acid) acid
stearic acid (octadecanoic acid)
H CO
OH
CH3 CO
OH
CH3 CH2C
O
OH
CH3-(CH2)16-COOH
Unsaturated acidUnsaturated acidis an acid, which has both as simple bonds is an acid, which has both as simple bonds and duble bonds in molecule. Example:and duble bonds in molecule. Example:CHCH22=CH-COOH=CH-COOH
Aromatic Aromatic acidacid
is acid, which contain aromatic ring. is acid, which contain aromatic ring. Example: benzoic acid.Example: benzoic acid.
Monocarboxylic acidMonocarboxylic acid
is acid, which has one carboxylic group in is acid, which has one carboxylic group in molecule. Example: acetic acid, formic molecule. Example: acetic acid, formic acid, buthanic acid.acid, buthanic acid.
Dicarboxylic acidDicarboxylic acid
is acid, which has two carboxylic group in is acid, which has two carboxylic group in molecule. Example: oxalic acid, malonic molecule. Example: oxalic acid, malonic acid.acid.
The names of some saturated monocarboxylic acids
Structural formula Name of nomenclature
trivial substitute rational
formic acid methanoic acid -
acetic acid etanoic acid acetic acid
propionic acid propanoic acid methylacetic acid
oil acid butanoic acid ethylacetic acid
iso oil acid 2-methylpropanoic acid
dimethylacetic acid
valeric acid pentanoic acid propylacetic acid
iso valeric acid 3-methylbutanoic acid
methylethylacetic acid
CH3-(CH2)4-COOH capronic acid hexanoic acid n-butylacetic acid
CH3-(CH2)10-COOH lauric acid dodecanoic acid
CH3-(CH2)12-COOH myristic acid tetradecanoic acid
CH3-(CH2)14-COOH palmitic acid hexadecanoic acid
CH3-(CH2)16-COOH stearic acid octadecanoic acid
CO
OHCH3
CH3 CH CH2
1234
CH3 CH2C
O
OHCH2 CH2
CH3 CH CO
OH
CH3
123
CH3 CH2C
O
OHCH2
CH3 CH2C
O
OH
CH3 CO
OH
H CO
OH
The names of some unsaturated monocarboxylic acids
Structural formula Name of nomenclature
trivial substitute
CHCH22=CH-COOH=CH-COOH acrylic acid propenoic acid
methacrylic acid 2-methylpropenoic acid
CHCH22=CH-CH=CH-CH22-COOH-COOH vinyl acetic acidvinyl acetic acid 3-butenoic acid
crotonic acid trans-2-butenoic acid
iso crotonic acid cus-2-butenoic acidcus-2-butenoic acid
propiolic acid propionoic acid
tetrolic acid 2-butynoic acid
oleic acid cus-9-octadecenoic acid
Linoleic acid cus-9-cus-12-octadecadienoic acid
linolenic acid cus-9-cus-15-octadecatrienoic acid
CH
CCH2 COOH
3
C CCOOH
H
H
CH3
C CH
COOH
H
CH3
CH C COOH
C COOHCCH3
4 3 2 1
CH
CH (CH2)7 CH3
(CH2)7 COOH
CH
CH
(CH2)4CH3
CH2CH
CH (CH2)7 COOH
CH
CH3
CH2
CH2CH
CH CH2
COOH
CHCH
CH (CH2)7
The names of some dicarboxylic acids
Structural formula Name of nomenclature
trivial substituteHOOC-COOH oxalic acid ethandioic acidethandioic acid
HOOC-CH2-COOH malonic acidmalonic acid propandioic acidpropandioic acid
HOOC-CH2-CH2-COOH succinic acid butandioic acidbutandioic acid
HOOC-CH2-CH2-CH2-COOH glutaric acid pentandioic acidpentandioic acid
HOOC-CH2-CH2-CH2-CH2-COOH adypinic acid hexandioic acidhexandioic acid
HOOC-(CH2)5-COOH pimelic acid heptadioic acidheptadioic acid
HOOC-(CH2)6-COOH cork acid octandioic acidoctandioic acid
maleic acidmaleic acid cus-butendioic acidcus-butendioic acid
fumaric acid trans-butendioic acid trans-butendioic acid
phthalic acid 1,2-benzoldicarbonic acid1,2-benzoldicarbonic acid
iso iso phthalic acid 1,3-benzoldicarbonic acid1,3-benzoldicarbonic acid
C C
COOHHOOC
HH
C C
HOOC
HCOOH
H
COOH
COOH
COOH
COOH
Methods of preparation of carboxylic acids.Methods of preparation of carboxylic acids.
1. Oxidation of alkylbenzenes.
2. Oxidation of primary alcohols.
3. Oxidation of aldehydes.
44. Synthesis of carboxylic acids by the hydrolysis of nitriles.. Synthesis of carboxylic acids by the hydrolysis of nitriles.
Properties of Carboxylic AcidsPhysical Properties of Carboxylic Acids
Formula IUPAC Name Melting Point Boiling Point
HCO2Hmethanoic
acid8.4 ºC 101 ºC
CH3CO2H ethanoic acid 16.6 ºC 118 ºC
CH3CH2CO2H propanoic acid -20.8 ºC 141 ºC
CH3(CH2)2CO2H butanoic acid -5.5 ºC 164 ºC
CH3(CH2)3CO2H pentanoic acid -34.5 ºC 186 ºC
CH3(CH2)4CO2H hexanoic acid -4.0 ºC 205 ºC
CH3(CH2)5CO2H heptanoic acid -7.5 ºC 223 ºC
CH3(CH2)6CO2H octanoic acid 16.3 ºC 239 ºC
CH3(CH2)7CO2H nonanoic acid 12.0 ºC 253 ºC
CH3(CH2)8CO2H decanoic acid 31.0 ºC 219 ºC
Solubility of carboxylic acids
Chemical properties of carboxylic acids.Chemical properties of carboxylic acids.
Reduction reaction.
Carboxylic acids are reduced to primary alcohols by the powerful reducing agent lithium aluminum hydride.
Salt formationSalt formation
Magnesium acetate
Calcium acetate
Sodium butanoate
αα-halogenation of carboxylic acids-halogenation of carboxylic acids This method of α bromination of carboxylic acids is called the
Hell–Volhard– Zelinsky reaction.
R-COH
O SOCl2R-C
Cl
O
R1OHR-C
O-R1
O
R1SHR-C
S-R1
O
R-CO
O
ONH3
R-CNH2
O
R-CNR2
O
P2O5
R-CO
O
O
R1OH
R-CO-R1
O
H2O
R1-COONа
R1-C
R2-NH
R1-C
H2O
1
2
3
4
5окрім реакції (3)
H2O
Except reaction 3
Substitution of the Hydroxyl GroupSubstitution of the Hydroxyl Group
1. 1. ESTERIFICATIONESTERIFICATION
This page looks at esterification - mainly the This page looks at esterification - mainly the reaction between alcohols and carboxylic acids reaction between alcohols and carboxylic acids to make esters.to make esters.
2. Formation of acyl chlorides. Formation of acyl chlorides. Thionyl chloride reacts with carboxylic acids to yield acyl chlorides.
RReaction with halo-compoundseaction with halo-compounds::
3. 3. Preparation of Acid AnhydridesPreparation of Acid Anhydrides
4. The formation amides.4. The formation amides.
H2C
H2C
C
C
OH
OH
O
O
+ NH3
t
O
O
N H + H2O
succinic acidsukcynimide
Formation of the biuret and a biuret reaction
urea
Decarboxylation of carboxylic acids. The loss of a molecule of carbon dioxide from a carboxylic acid is
known as decarboxylation.
C6H5COOH
benzoic acid
NaOHC6H5COONa + H2O
C2H5OH; H+C6H5 C
O
OC2H5
ethylbenzoath
PCl5C6H5 C
O
Clbenzoilchloride
(CH3CO)2O; H+
C6H5 C
O
OC
O
C6H5
+
+ +
+
H2O
HCl POCl3
CH3COOH2
anhydride of benzoic acid
HOOC CH2 CH2 COOH
succinic acidHOOC CH CH COOH
Br Br-dibromsuccinic acid
HOOC CH CH2 COOHchlorsuccinic acid
H2
Br2
HCl
COOH
CH
CH
COOHbutendioic acid
HOH; H+
[O]
KMnO4
HOOC CH CH2 COOH
malic acid
HOOC CH CH COOH
racemic acid
2, 3
8. Carboxylic acid derivatives.8. Carboxylic acid derivatives.
These classes of compounds are classified as carboxylic acid derivatives. All may be converted to carboxylic acids by hydrolysis.
Functional groups are groups of atoms found within molecules that are involved in the chemical reactions characteristic of those molecules.
There are mono-, poly- and heterofunctional group in the structure of organic compounds:Monofunctional group – contains only 1 functional group.
C2H5—OH
Polyfunctional group – contains several similar functional group.H2C
CH
H2C
OH
OH
OH
Heterofunctional group – contains several different functional group.
Sphingosine
Biological role:Biological role: Heterofunctional compounds are widespread in the Heterofunctional compounds are widespread in the
nature. They are in fruits and vegetable leafs. Also nature. They are in fruits and vegetable leafs. Also they are formed in body. So, the lactic acid is they are formed in body. So, the lactic acid is product of transformation glucose (glycolysis) in product of transformation glucose (glycolysis) in human body. A malic and citric acid formed in a human body. A malic and citric acid formed in a cycle of tricarboxylic acids, which is also known as cycle of tricarboxylic acids, which is also known as citric acid cycle or Krebs' cycle. Hydroxo acids citric acid cycle or Krebs' cycle. Hydroxo acids such as: pyruvic acid, acetoacetic acid, oxaloacetic such as: pyruvic acid, acetoacetic acid, oxaloacetic acid, acid, -ketoglutaric acid are important in -ketoglutaric acid are important in metabolism of carbohydrates.metabolism of carbohydrates.
HydroxyacidsHydroxyacids HydroxyacidsHydroxyacids are the derivatives of carboxyl acids that are the derivatives of carboxyl acids that
contain –OH group (1 or more).contain –OH group (1 or more).
3 2 1CH3C CH
O
OHOH
β α
2-hydroxypropanoic acidα-hydroxypropanoic acid
tartaric acidα,α’-dihydroxysuccinic acid,2,3-dihydroxybutandioic acid,
lactic acid,α- hydroxypropanoic acid,2- hydroxypropanoic acid
malic acid,hydroxysuccinic acidhydroxybutanedioic acid
citric acid,2-hydroxy-1,2,3-propantricarboxylic acid
glycolic acid,hydroxyacetic acid,hydroxyethanoic acid
Methods of preparation of hydroxyacids:1.1. Hydrolysis of α-halogenoacidsHydrolysis of α-halogenoacids
2.2. Oxidations of diols and hydroxyaldehydesOxidations of diols and hydroxyaldehydes
3.3. Hydration of α,β-unsaturated carboxylic acidsHydration of α,β-unsaturated carboxylic acids
4.4. Hydrolysis of hydroxynitriles (cyanohydrins)Hydrolysis of hydroxynitriles (cyanohydrins)
CH3C CH
O
OHCl
NaOHH2O CH3C CH
O
OHOH
NaCl+ + lactic acidlactic acid
CH3C CH
O
HOH
CH2H3C CH
OHOH
CH3C CH
O
OHOH
[O] [O]
CH CO
OHH2O+CH2 CH2C CH2
O
OH
H+
OH
ββ-hydroxypropanoic acid-hydroxypropanoic acid
Physical and chemical properties of
hydroxycarboxylic acid For For physical propertiesphysical properties of hydroxycarboxylic acids are of hydroxycarboxylic acids are
colorless liquids or crystalline substance, soluble in water.colorless liquids or crystalline substance, soluble in water.
Chemical properties:Chemical properties:
Carboxyl group can react forming:Carboxyl group can react forming:
a) salts:a) salts:H2C CH2 C
O
OHOH
NaOH H2C CH2 CO
ONaOH
H2O+ +
sodium sodium ββ-hydroxypropanoic acid-hydroxypropanoic acid
2 H2C CH2 CO
OHOH
2 Na 2 H2C CH2 CO
ONaOH
H2+ +
2 H2C CH2 CO
OHOH
MgO
H2C CH2 CO
OMg
O
CO
H2C CH2
OH
OH
H2O+ +
H2C CH2 CO
OHOH
NaHCO3 H2C CH2 CO
ONaOH
H2CO3
H2O CO2
++
Ester formation:H2C CH2 C
O
OH++
OH
H2OHO CH3 H2C CH2 CO
OOH
CH3
Methyl-Methyl-ββ-hydroxypropanoate-hydroxypropanoate
Methyl-Methyl-ββ-methoxylpropanoat-methoxylpropanoat
ββ-ethanoatepropanoic acid-ethanoatepropanoic acid
c) Amides formation:c) Amides formation:
II. –OH group reaction:II. –OH group reaction:
a) hydrohalogens (HCl, HBr, HI, HF)a) hydrohalogens (HCl, HBr, HI, HF)
b) can oxidize
H2C CH2 CO
OH+NH3+
OH
H2C CH2 CO
NH2OH
H2Ot=200o
amide of amide of ββ-hydroxypropanoic acid-hydroxypropanoic acid
HCl ++ H2OH2C CH2 CO
OHCl
CH2C CH2
O
OHOH
+ H2OCH2C CH2
O
OH
[O]
OH
CHC CH2
O
OHO
ββ-oxopropanoic acid-oxopropanoic acid
lactic acid lactide
Related to heat of:
1. α-hydroxyacids
2. β-hydroxyacids
3. γ-hydroxyacids
H
O
C
O H
C H 3
O
C
H
+
O
O H
CС H 3 С
O H
H
H 2S O 4к .
t
HCOOH CO + H2Oк. Н2SO4, t
Ñ ÑH2COOHHOOCH2C
OH
COOH
H CO
OHC CH2COOH
O
HOOCH2C
C CH3CH3
O
ê. H2SO4 +
CO H2O 2 CO2
t acetidicarbonic acid
Decomposition α-hydroxyacids
Ethanal
formic acid
Phenolacids.Phenolacids.
o-hydroxycinnamic acid salicylic acid,2-hydroxybenzoic acid
4-hydroxybenzoic acid
3,4,5-trihydroxybenzoic acid,gallic acid
PhenolacidsPhenolacids are the derivatives of aromatic carboxyl acids that are the derivatives of aromatic carboxyl acids that contain –OH group (1 or more).contain –OH group (1 or more).
COOH
OH OH
COONa+ CO2+ NaHCO3 + H2O
salicylic acid
Phenolacids are the derivatives of aromatic carboxyl acids that contain –OH group (1 or more).
Decarboxylation
Representatives of hydroxyacids: Lactic acid is a trivial name because
at first it was extracted from milk. It is present in yogurt, sour milk and other milk products. It can form in muscles during hard and prolonged work. Salts of milk acid are used in medicine.
Malic acid. It is present in green apples and
some berries. It takes part in biological processes in human organisms and organisms of other alive creatures. It is used in medicine for synthesis of some medical preparations.
Tartaric acid . It is present in grape. It is used in medicine for synthesis of some
medical preparations.
CH3C CH
O
OHOH
CH2 CO
OHCHC
O
HOOH
CH
CH
C
C
OH
OH
O
OH
O
OH
Citric acidCitric acid . It . It is present in is present in orange, lemon and other orange, lemon and other
citric fruits. It takes citric fruits. It takes part in part in biological biological processes in processes in human human organism.organism.
HO C
CH2
C
CH2OH
O
C
C
O
OH
O
OH
OxoacidsOxoacidsTo oxoacids include aldehydo- and ketonoacids. These compounds include in the structure of the carboxyl group, aldehyde functional group or ketone functional group.
γ-ketovaleric acid,4-oxopentanoic acid,levulinic acid
acetoacetic acid,3-oxobutanoic acid,β-ketobutyric acid
oxalacetic acid,oxobutanedioic acid,ketosuccinic acid
glyoxylic acid,oxoethanoic acid
Pyroracemic (pyruvic) acid,2-oxopropanoic acid
ketoglutaric acid
Chemical properties of oxoacidsChemical properties of oxoacids1.1. Decarboxylation of Decarboxylation of αα-oxoacids-oxoacids
2.2. Decarboxylation of Decarboxylation of ββ-oxoacids-oxoacids
CH3 C
O
COOHconc. H2SO4, t
CH3 C + CO2
O
Hpyroracemic acid acetaldehyd
CH3 C
O
t
acetoacetic acid
CH2 COOH CH3 C CH3
Oacetone
- CO2
Thank you for attention