3.3.14-Organic Synthesis Flashcards
What needs to be thought of in organic synthesis
- Reagents required
- Presence of other functional groups
- conditions required
- rate of reaction
- yield
- atom economy
- Costs , plants, chemicals
- safety, toxicity, flammability
- problems of purification
- possibility of optical activity
Problems of chiral compounds
May not be as effective -higher dosage
Cause dangerous side effects
Consequences of chiral compounds
Isomers have to be separated to obtain effective result
Separation can be expensive and complicated
Non separation lead to larger dosage being used cause side effects
Solutions to chiral compounds
Use natural chiral compounds as starting
Use reactions that give specific isomers
Catalysts to give specific isomers
Enzyme or bacteria which are stereoselective
Thermal cracking reaction
Alkane to alkanes,alkenes
Need high T,high P
Catalytic cracking reaction
Alkane to alkenes and branched alkanes
High T , zeolite
Complete combustion
Alkanes to water and carbon dioxide
Need excess O2
Reaction of free radical substitution
CH4 to CH3Cl +HCl
Cl2 UV light
Alkene reaction hydrogenation
H2/Ni 150C
C2H4 to C2H6
Alkene reaction with Br2
C2H4 to CH2BrCH2Br
Br2 room temp
Electrophilic addition
Alkene reaction with HBr
C2H4 to CH3CH2Br
HBr room temp
Electrophilic addition
Alkene reaction with conc H2SO4
Alkene to CH3CH2-O-SO3H
Electrophilic addition
Conc H2SO4
Alkene reaction with H2O
C2H4 to CH3CH2OH
H3PO4 ,high T , high P
Hydration
What is the reaction when
CH3CH2-O-SO3H +H2O and what does it make
Hydrolysis
To make CH3CH2OH
CH3CH=CH2
To make CH3CH(OH)CH3
1) conc H2SO4
Electrophilic addition
2) H2O
Hydrolysis
CH3CH=CH2 to CH3CH(Br)CH3
HBr room temp electrophilic addition
Haloalkane to CH3CH2CN +KBr
KCN , ethanol
Nucleophilic substitution
Haloalkane to CH3CH2OH +NaBr
NaOH/KOH
Warm/aq
Nucleophilic substitution
Haloalkane to CH3CH2NH2
Ammonia
Ethanol/high p
Nucleophilic substitution
Haloalkane to CH2=CH2
KOH ethanol
Elimination