ORGANIC CHEM REACTIONS Flashcards
How to prepare alkanes
Reduction of alkenes
H2 gas with Ni catalyst and heat or Pt/Pd catalyst at rtp
What do alkanes form
Halogenoalkanes
Excess halogen or alkane depending on product, UV light/heat
How to prepare alkenes
1.Dehydration of alcohols
Excess conc H2SO4 and heat or Al2O3 and heat
2.Dehydrohalogenation of halogenoalkanes
NaOH or KOH in alcohol and heat
What do alkenes form
1.Halogenoalkanes
HX at rtp
2.Di-substituted halogenoalkanes
X2 in CCl4 solvent at rtp
3.Alcohol with halogen subbed
X2 in water at rtp
4.Alcohol
cold conc H2SO4, followed by heat with water
5.Diol
KMnO4 in NAOH at cold or rtp
6.Carboxylic Ketone or CO2
KMnO4 in H2SO4 and heat
How to test for alkenes
Decolorization of a solution of orange-red Br2 in CCl4 or orange Br2 in H2O
What does benzene form
- Halogenation to form benzene with halogen sub
X2 gas with anhydrous FeCl3 at rtp - Alkylation to form methylbenzene for eg
RX with anhydrous AlCl3 at rtp
3.nitrobenzene
conc HNO3 acid with conc H2SO4 as catalyst heat at 60 degrees under reflux
4.cyclohexane
hydrogen gas with Ni catalyst at 150 degrees and high pressure
What does methyl benzene form that is diff from benzene
1.nitrobenzene can occur at lower temp of 30 degrees
2.side chain oxidation to aldehyde with weak OA and Carboxylic with benzylic H
KMnO4(aq) with H2SO4(aq)
How to prepare halogenoalkanes
- From alkenes
HX at rtp - From alcohols
PX3, SOCl2 and HX and heat under reflux or PCl5 at rtp
What can halogenoalkanes form
Nucleophilic sub
1. Form alcohol
NaOH or KOH with heat under reflux
- Form nitriles
alc KCN with heat under reflux - Form amine
alc NH3 in excess heated under pressure in a sealed tube
Elimination to form alkene
alc NaOH or KOH with heat under reflux
How to test for RX
1.Heat with NaOH(aq)
2.Acidify with dilute HNO3
3.Add aq AgNO3
white if Cl
cream if Br
yellow if I
How to form alcohols
1.From halogenoalkanes
NaOH(aq) or KOH(aq) and heat under reflux
2.From alkenes
cold conc H2SO4 followed by H2O warm
3.Reduction from carboxylic acids, aldehydes and ketones
LiAlH4 in dry ether (works for all), NaBH4 in methanol or H2 with Pt
What do alcohols form
- Halogenoalkanes
PX3, PCl5 and SOCl2 all with heat - Alkenes
excess conc H2SO4 and heat - Redox with reactive metal to give salt
- Carbonyl compounds and carboxylic acids
K2Cr2O7 and H2SO4 with heating under reflux (heat under immediate distillation for aldehyde) - Esters with Acyl chlorides and carboxylic acids
conc H2SO4 and heat - Tri-iodomethane formation
I2 in NaOH(aq) and heat
What do phenols form
- Salts with reactive metals or acid base
- mono or tri subbed nitrophenol
dilute HNO3 for mono and conc for tri - mono or tri subbed bromophenol or any halogen
Br2 in CCl4 solvent for mono and in aq for tri
How to test for alcohols
reactive metal producing hydrogen gas
How to test for phenol
aq FeCl3 forming a violet colouration