ORGANIC CHEMISTRY —— SUMMARY
Organic Compound
1 Alkane
○
Type of Reaction
a) combustion or incomplete (CO/C+H2O)
(alkane +O2 → CO2 + H2O)
b)free radical substitution
(alkane → RX)
c)cracking
(lone alkane → short alkane+ short alkenes or
H2)
Reagent/s
Condition/s
Example
Mechanism
Excess O2
Burn
C2H6 + 7/2O2 → 2CO2 + 3CO2
——
X2 = Cl2, Br2
UV light
CH3CH3 + Cl2 → CH3CH2Cl + HCl
Free radical
substitution
——
Al2O3[SiO2]
450℃
H2(g)
Ni/heat
X2=Cl2, Br2, I2(in
CCl4)
HX = HCl, HBr, HI
Dark
Room temp
Room temp
H3PO4/300℃
/70 atm
a)electrophilic addition
Ⅰ H2 ( Alkene → Alkane)
Ⅱ X2 ( Alkene → RX2)
Ⅲ HX ( Alkene → RX)
Ⅳ steam/H2O(g) ( Alkene → ROH)
2 Alkene
○
b)oxidation
Ⅰ alkene → diol
Ⅱ alkene → ketone/CO2/carboxylic acid
steam/H2O(g)
H+/ KMnO4
+
H / KMnO4
cold, dilute
hot,
concentrated.
C10H22 → C4H8 + C6H14
Or C10H22 → C4H8 + C6H12 +H2
——
CH2=CH2+H2 → CH3CH3
CH2=CH2 + Br2 → CH2BrCH2Br
Electrophilic addition
CH2=CH2 + HBr → CH3CH2Br
CH2=CH2 + H2O → CH3CH2OH
CH2=CH2 + H2O +[O] → CH2OHCH2OH
H 3C
H
——
H
C C
H
+ 5[O] → CH3COOH +CO2 + H2O
c)addition polymerization
H H
——
——
C C
nCH2=CH2 →
Ⅰ ethene → polyethene
n
H H
——
H H
Ⅱ chloroethene → pvc
a)nucleophilic substitution
ⅠHydrolysis
R-X → R-OH
Ⅱnitrile formation
3 Halogen derivation
R-X → R-CN
○
Ⅲ amine formation
R-X → R-NH2
b)elimination
R-X → alkene
——
——
C C
nCH2=CHCl →
NaOH(aq)
KCN(ethanol)
conc. NH3(ethanol)
NaOH (alcohol)
aq
heat [reflux]
ethanol
heat [reflux]
heat in a sealed
tube
alcohol +
reflux
n
H Cl
CH3CH2Br + NaOH → CH3CH2OH + NaBr
CH3CH2Cl + KCN → CH3CH2CN + KCl
Nucleophilic
substitution
CH3CH2Br + NH3 → CH3CH2NH2 + HBr
CH3CH2Br + NaOH → CH2=CH2 + NaBr + H2O
——
4 Alcohol
○
a)combustion
(R-OH → CO2 + H2O)
b)nucleophilic substitution
(R-OH → R-X)
c)acid/metal reaction
(R-OH → R-O-Na+)
d)oxidation
R-OH (1°) → RCHO → RCOOH
R1
R2
O
CH(OH)
R1 C R2
(secondary alcohol)
e)elimination
(R-OH → alkene)
a)reduction
aldehyde → 1°RCH2OH
ketone → 2°R1CH(OH)R2
excess O2
burn
PCl3,PBr3,PI3
orPCl5 or SOCl2
PCl5,SOCl2 RT
Na
room temp
K2Cr2O7/H+
distill--RCHO
reflux -acid
CH3CH2OH + 2[O] → CH3COOH+H2O
CH3CH2OH +[O]----->CH3CHO +H2O
heat [reflux]
CH3CH(OH)CH3 + [O] → CH3COCH3 + H2O
K2Cr2O7/H+
conc. H2SO4/conc.H3PO4
or hot AL2O3
CH3CH2OH + 3O2 → 2CO2 + 3H2O
Nucleophilic
substitution
CH3CH2OH + PCl5 → CH3CH2Cl + POCl3 + HCl
CH3CH2OH + Na → CH3CH2O-Na+ + 1/2H2
heat
NaBH4 or LiAlH4
NaBH4 or LiAlH4
HCN
——
——
CH3CH2OH → CH2=CH2 + H2O
——
CH3CHO + 2[H] → CH3CH2OH
CH3COCH3 + 2[H] → CH3CH(OH)CH3
——
O
NaCN catalyst
room temp
bubbles
OH
H 3C C H
+ HCN
H 3C C H
CN
b)nucleophilic addition
O
Nucleophilic addition
OH
H3C C CH3
+ HCN
H3C C CH3
CN
5 Carbonyl compound
○
O
c)addition-elimination
carbonyl compounds → orange ppt.
2,4-DNPH
Room
temperature
H NO2
H
H3C C CH3
+
H3C
N N
H
H NO2
C N N
NO2
d)oxidation [only aldehyde]
Ⅰ RCHO → RCOOH
6 Nitriles R-CN
○
K2Cr2O7/H+
orange ppt
H3C
heat
CH3CHO + [O] → CH3COOH
NO2
Ⅱ RCHO → R-COOH/R-COO-
Fehling’s reagent
warm
CH3CHO + 2Cu2+ +5OH- → CH3COO- + Cu2O + 3H2O
Ⅲ RCHO → R-COOH/R-COO-
Tollen’s reagent
[ammonical AgNO3]
warm
CH3CHO + 2[Ag(NH3)2]+ +3OH- → CH3COO- + 2Ag +
4NH3 +2H2O
dilute HCl/H2SO4
Heat and reflux
hrdrolysis
R-CN → R-COOH
CH3CN +2H2O + HCl→ CH3COOH + NH4Cl
——
——
a)acid/metal reaction
(R-COOH → R-COO-Na+/salt)
7 Carboxylic acid
○
R-COOH
b)neutralisation
(R-COOH → R-COO-Na+)
c)esterification
(R-COOH → R-COO-R)
8 esters
○
R-COO-R
a)acid hydrolysis
(R-COO-R1 → R-COOH + R1-OH)
b)alkaline hydrolysis
(R-COO-R1 → R-COO- + R1-OH)
reduction of carboxylic acid to primary alcohol
reducing agent : LiALH4
room temp
CH3COOH + Na → CH3COO-Na+ + 1/2H2
NaOH or Na2CO3
room temp
CH3COOH + NaOH → CH3COO-Na+ + H2O
2CH3COOH + Na2CO3 → 2CH3COO-Na+ + H2O + CO2
alcohol
[e.g. C2H5OH]
conc. H2SO4
catalyst/reflux
dilute H2SO4(aq)
heat
Na
CH3COOH + C2H5OH
CH3COOCH2CH3 + H2O
——
CH3COOCH2CH3
CH3COOH + C2H5OH
——
dilute NaOH(aq)
heat
CH3COOCH2CH3 + NaOH
-
+
CH3COO Na + C2H5OH
IDENTIFICATION TEST
Identification tests
Reagents and conditions
Functional Group
1. alkenes C=C
(unsaturated hydrocarbon)
1 add Br2 water under dark condition
○
2 add KMnO 4 /acid under cold/dil. conditions
○
or KMnO4/alkaline under hot/conc. conditions
Observation
Br 2 water turns from brown to colourless
purple color of KMnO4 decolorize
Remarks
diagnostic test(for unsaturation)
——
white ppt. ( R-Cl)
2. Halogen derivatives R-X
1 add ethanol, then add AgNO 3 (aq)
○
cream ppt. ( R-Br)
diagnostic test(for unsaturation)
yellow ppt. ( R- I)
3. alcohol R-OH
1 add anhydrous PCl 5
○
white steamy fumes of HCl
diagnostic test
2 add Na
○
H2(g)
——
3 add acid/KMnO4 [heat]
○
purple colour of KMnO4 decolourise
——
4 add acid/K 2Cr2O7 [heat]
○
orange colour of K2Cr2O7 becomes green
——
5 add carboxylic acid with conc. H2 SO4 and boil
○
fruit/sweet smell
——
add 2,4-DNPH
orange/yellow ppt. [crystals]
1 add acid/ K2Cr2O 7 [heat]
○
orange colour of K2Cr2O7 becomes green
2 add Fehling’s reagent and warm
○
brick red ppt.
diagnostic test
silver mirror
diagnostic test
4. carbonyl compounds [ aldehydes/ketones ]
O
O
diagnostic test
R C H R C R
5. aldehydes
O
R C H
3 add Tollen’s reagent [ammonical AgNO3 ] and
○
warm
6. carboxylic acids
O
R C O H
7. Iodoform CH3CO- and CH3CH(OH)-
1 add Na
○
H2
2 add Na 2CO3
○
CO2 [lime water turns milky]
3 add alcohol with conc. H2 SO4 and boil
○
fruit/sweet smell
add NaOH +I2
yellow PPT CHI3
——
——
diagnostic test
——
diagnostic test