Carbonyl compounds

Carbonyl compounds

The Carbonyl group
1. C==O
  1. Aldehyde-......al Ketone-.......one Carboxyllic acid-.........anoic acid Acyl chloride-........anoyl chloride Amide-.......amide Ester......anoate
Alcohols from aldehydes and ketones
1. Primary alcohols oxides to aldehydes and secondary to ketones
  1. Acidified potassium dichromate with sulfuric acid - in equation just add (O) and make H20 in equation
    1. Orange to green colour change
  2. ROH+2(O)=RCOOH+H2O
2. Nucleophilic addition - C==0 becomes polar - eectronegativity so the C can be attacked by nucleophiles e.g. H-
  1. : to C and == to O
    1. O:- to H+
    2. Same mechanism
      1. Forms 2-hydroxy...........nitrile
  2. RCHO+2(H)=RCH2OH
Hydroxynitriiles from aldehydes and ketones
1. Same but
2. RCHO+HCN=RCH(OH)CN
3. Can be turned into carboxylic acid
  1. RCH(OH)CN+H2O+H+=RCH)OH)COOH+NH4+
Esterification
1. Test for carboxylic acids - reaction with carbonates - effervescence
2. Carboxylic acids + alcohol = ester + water
  1. RCOOH+ROH=RCOOR+H2O
  2. The OH from the carboxylic acid and H from alcohol for the H20
3. Name the bit next to the 0 and then the other bit and add oate
Uses of esters
1. Food flavourings
  1. Manufacturing costs a lot less than extracting
2. Plasticizers
  1. Added to polymers to let the molecules slide over each other more easily
    1. Makes it ofter and more flexible e.g. PVC and uPVC
Oil fats and biodiesel
1. Acid catalysed hydrolysis
  1. Heating under reflux conditions with dilute HCl
    1. RCOOR+H2O=RCOOH+R2OH
      1. Lies to the left so doesn't work very well
2. Base catalysed hydrolysis
  1. Heating under reflux conditions with NaOH
    1. RCOOR+NaOH=RCOO-Na++ROH
      1. Lies to the right so works better but makes and acid and a salt
3. Vegetable oil
  1. Triglycerols - triester
    1. Hydrolysed by heating with 3NaOH
      1. produces glycerol and sodium carboxylate
        Glycerol used in cosmetics and toothpaste
        Sodium carboxylate used as soap - long chain represents the hydrophobic end as its non polar so dissolves in oil and greece
    2. Biodiesel
      1. Heating with 3methanol and 3NaOH
        Base-catalysed tranesterification
        Makes methyl ester(biodiesel) lays on top as it's denser and glycerol

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	Creado por charlotte_1995 hace casi 11 años