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
Nitrile to CH3CH2CH2NH2
LiAlH4
Ethoxyethane
Reduction
Primary alcohol to Aldehyde
K2Cr2O7 / H+ distill off
Oxidation
Primary alcohol to alkene
Conc H2SO4 180C
Dehydration/elimination
Primary alcohol to R-COO- CH2CH3
R-COCl
Nucleophilic addition elimination
Primary alcohol to CH3COOCH2CH3 + H2O
Ethanoic acid
Conc H2SO4
Esterification
Secondary alcohol to CH3CHOCH3 (ketones)
K2CR2O7/H+
Oxidation
Secondary alcohol to CH3CH=CH2
Conc H2SO4
180
Dehydration
Carboxylic acid to CH3COONa +CO2+H2O
NaHCO3 room temp
Acid base
Carboxylic acid to CH3COOR +H2O
ROH conc H2SO4
Esterification
CH3COOR to CH3COONa + ROH
NaOH reflux
Hydrolysis
Aldehydes to CH3CH(OH)CN
KCN
Add HCl in situ
Nucleophilic addition
CH3CH(OH)CN To CH3CH(OH)CH2NH2
LiAlH4
Ethoxyethane
Reduction
Aldehyde to CH3COOH
Fehlings solution
Heat
Oxidation
Aldehyde to CH3CH2OH
NaBH4 aq,warm Reduction Or H2/Ni 150 Reduction
Ketone to (CH3)2C(OH)CN
HCN from KCN and HCl
Nucleophilic addition
Ketone added fehlings solution
No reaction
Ketone to CH3CH(OH)CH3
NaBH4 Nucleophilic addition Or H2/Ni 150 Reduction
C6H6 to C6H6NO2
Conc HNO3 and conc H2SO4
Nitration
C6H6 to C6H12
H2/Ni
150
Reduction
C6H6 to C6H5COCH3 +HCl
CH3COCl /ALCl3
Electrophilic substitution
Amino acid — H3N+CH2COOH
HCl
Acid base
Amino acid to H2NCH2COO-
NaOH
Acid base
Amino acid to H2nCH2COOCH3 +H2O
CH3OH
Conc H2SO4
Esterification
Amino acid to CH3CONHCH2COOH
CH3COCl room temp
Acylation
Amino to H2NCH2COHNCH2COOH
Amino acid
Condensation
Test
Bromine water
Add Br 2
Tests for C=C
Orange to colourless positive
Acidified K2CR2O7 test
Heat K2Cr2O7/H+ Test for Primary, secondary alcohol Aldehydes Go orange to green
Tollens reagent test
Warm AgNO3
NaOH and NH3
Aldehydes
Silver mirror
Fehlings solution test
Fehlings A and B boil
Blue to brick red
Tests for aldehydes
Hydrolysis followed by acidified AgNO3 year
NaOH heat then add AgNO3 Tests for haloalkane Cl - white Br- cream I - yellow
Hydrolysis test
Add H20
Test for acyl chloride
Steamy misty fumes
