Alcohol + carboxylic acid --> polymer with ester link + waterAlcohol + acid chloride --> ester link + HClAmine + carboxylic acid --> amide/peptide link + waterAmine + acid chloride --> amide/peptide link + HCl
Slide 5
Amides
Acyl chloride + ammonia --> amide + HCl (preferred method of making amides as it is a violent reaction).Carboxylic acid + ammonia (heat)--> salt (heat)--> amideKetone + ammonia --> amide + OH-RKetone + amine --> secondary amide with amide/peptide link
Slide 6
Amide Hydrolysis
A = Aqueous sulfuric acid (acidic condition) --> carboxylic acid + ammonium (acid formed in acidic condition)B = Aqueous sodium hydroxide (basic condition) --> carboxylate ion (with Na+) + ammonia (base is formed in basic condition - acid donated H+ ion in basic condition)
Slide 7
Hydrolysis of polymer w/ amide link
A = Aqueous sulfuric acid (acidic condition) --> carboxylic acid + R-NH3+ (basic end of molecule NH2 accepts H+ to become NH3+)B = Aqueous sodium hydroxide (basic condition) --> carboxylate ion (with Na+) + R-NH2 (base is formed in basic condition - acid part donates H+)
Slide 8
Hydrolysis of protein (breaking amide/peptide link)
A = Aqueous sulfuric acid (acidic condition) --> HOCH2-CH(NH3+)-COOH + COOH-CH2-NH3+ (amine is base so accepts H+ to become NH3+)B = Aqueous sodium hydroxide (basic condition) --> HOCH2-CH(NH2)-COO-(Na+) + NH2-CH2-COO-(Na+) (acidic end of acid donated H+ - base end formed in basic condition)
Slide 9
Aldehydes
Can be oxidised to form carboxylic acids.
Acidified dichromate (orange --> green)
Acidified permanganate (purple --> colourless)
Tollen's Reagent Ag+ (aq) + e- --> Ag (s) (colourless --> thin black precipitate or silver mirror)
Fehlings/Benedicts Cu2+ --> Cu2O (blue --> brick red)
Can be reduced back to primary alcohol using NaBH4.
Slide 10
Ketones
NO FURTHER OXIDATIONCan be reduced back to secondary alcohol using NaBH4*Still mention negative test result*e.g. this is a ketone because there was no colour change
Slide 11
Lucas Reagent ZnCl2/HCl conc.
ZnCl2 is a catalyst, HCl does the reducing.Lucas Reagent is used to distinguish alcohols.Alcohol --> HaloalkaneColourless --> Cloudy (due to insoluble haloalkane)Tertiary - fastestSecondary - slowerPrimary - no reaction
Slide 12
Alcohols
1. PRIMARY ALCOHOL oxidised by acidified dichromate/permanganate. First to an ALDEHYDE then to a CARBOXYLIC ACID.The reverse of this reaction is a reduction using NaBH4. The aldehyde is reduced to make a primary alcohol.2. SECONDARY ALCOHOL oxidised by acidified dichromate/permanganate to a KETONE.The reverse of this reaction, a reduction using NaBH4. The ketone is reduced to make a secondary alcohol.3. Nucleophilic substitution by PCl3, PCl5 or SOCl2 to make a HALOALKANE - works best with primary or secondary4. Elimination by concentrated sulfuric acid forms an ALKENE (water removed). If asymmetrical, major and minor product formed using Markovnikof's Rule.5. Addition to ALKENE to make an ALCOHOL - dilute sulfuric acid or acidified H2O.This forms major and minor product (H atom goes onto carbon with more hydrogen atoms, OH goes on other carbon)6. Lucas Reagent (see slide)
PRIMARY AND SECONDARY ALCOHOLS WILL BE OXIDISED BY TOLLENS OR FEHLINGS/BENEDICTS.
Slide 13
Haloalkanes
1. Substitution KOH (aq) must be aqueous conditions, can use NaOH (aq) to make an ALCOHOL.2. Nucleophilic substitution NH3 in ethanol3. Substitution - bigger amine 4. Elimination KOH (alc) - forms major and minor product if asymmetrical
Slide 14
Carboxylic acids
1. Acid BaseAcid + Base --> Salt + WaterAcid + Carbonate --> Salt + Water + Carbon dioxide2. Substitution PCl5, PCl3 or SOCl2 to make an ACID CHLORIDE. Cannot be done with HCl as it contains water and would react violently. Ethanoic acid (R-COOH) -----> Ethanoyl chloride (R-COCl)3. Substitution NH3 - 2 stage reaction to make an AMIDE (slow reaction) Ethanoic acid + NH3 ------> Ethanoate ion (w/ NH4+) --(heat)---> Ethanamide (R-CONH2)