Esters Flashcards
(11 cards)
Nomenclature
What do you name the chain attached to the =O?
What do you name the chain attached to the
-O?
What do you name it if the benzene is attached to the =O?
What do you name it if the benzene is attached to the -O?
Alkanoate
Alkyl
Benzenoate
Phenyl
Physical Properties
What are they naturally?
Where do they naturally occur?
Are they miscible with water? Why?
Sweet smelling liquids
Fats and oils
No bc they have no hbonds
Hydrolysis
How is this done?
What does it form?
What is it essentially therefore?
Example with ethyl ethanoate
What is formed if you heat an ester with an alkali?
Example using ethyl ethanoate and NaOH
Name the carboxylate salt
Why is the ONa bond not represented with -?
With what is alkaline hydrolysis widely used?
What does this produce?
Reflux with dilute acid Carboxylic acid and alcohol Reverse esterification CH3CH2OOCH2CH3+H2O> CH3COOH+CH3CH2OH Carboxylate salt and alcohol CH3CH2OOCH2CH3+NaOH > CH3COONa+ + CH3CH2OH Sodium Ethanoate Because it's ionic not covalent Naturally occurring esters in animal fats and vegetable oils Useful products such as fat and glycerol
Oils and fats What are most of them? What are triesters? Draw example of a triglyceride What is the IUPAC name for glycerol? What do they have 3 strong of? Draw glycerol What are the 3 most common and what are they found in?
Triesters Triglycerides of the alcohol glycerol Propane-1,2,3-diol Strong carboxylic/fatty acid chains Oleic acid> olive oil and animal fats Steric acid> animal fats Unoleic acid> corn oil Alkaline hydrolysis Carboxylate salt and glycerol Saponification
How are triesters split?
What does this form?
What is this called?
Draw example with 16 CH2 in brackets
What are most soaps a mixture of? Why are they this mixture?
Alkaline hydrolysis
Carboxylate salt and glycerol
Saponification
Sodium salts of long chain carboxylic acids
Fats and oils they’re made from contain these mixtures
What are sodium salts?
What do they dissociate to form?
What is polar and what is non polar?
What mixes with what?
Ionic
Na+ and RCOO-
Long hydrocarbon chain polar COO- group non polar
Polar mixes with grease non polar mixes with water
Glycerol
What do its 3 OH form easily?
What do many of its applications depend on?
What is it used for in the cosmetic industry? Why?
What other uses does it have?(5)
Hbonds Ability to attract water Food and glue, prevents materials from drying too quickly Perfumes,food flavouring,cosmetics Surfactants Phosphoesters in DNA Organ solvents Plastics (polyesters)
Biodiesel Why is it environmentally good? Where is it from? How is a methyl esters mixture formed? In what is it used? Look at equation in notes
Is renewable
Oil in rape seed
Triglyceride ester + methanol with strong alkali catalyst
Vehicles
Acylation
What is the Acylation group?
What are two types and what are they derivates of? Draw the group
What do you add on the end to name each?
With a benzene?
What if there is an ethyl and a propyl group attached to the acid anhydride?
What are they useful as?
Why are they reactive?
What do these groups activate?
What is the carbonyl more susceptible as a result?
What happens to the nucleophile in the process?
What are possible nucleophiles?
COR Acyl chloride or acid anhydride Carboxylic acid COCl COOOC Oyl chloride Oic anhydride Bezenoic anhydride Bezenoyl chloride Intermediates Possess good leaving groups Cl- and -OCOR Adjacent carbon electron withdrawal Attack from a nucleophile Is acylated \:NRH2 :NH3 R:O:H H2:O:
Uses of Acylation
What is ethanoyl anhydride used on a large scale as? What is the general term for this?
Are acid anhydrides cheap or expensive?
What are acid anhydrides compared to acyl chlorides?(3)
Why are they less dangerous?
What is ethanoic anhydride used in the manufacture of? By what process? What’s the common name?
Word equation for acid anhydride plus alcohol
Example for acetyl salicylic acid
Ethanoylating agent
Acetylating agent
Cheap
Less corrosive
Less vulnerable to hydrolysis
Less dangerous
Because their by product is ethanoic acid rather than hydrogen chloride
Acetyl salicylic acid, aspirin, esterification
Acid anhydride+alcohol>ester + carboxylic acid
Ethyl anhydride + salicylic acid( benzene with COOH and OH attached) > acetyl salicylic acid(benzene with COOH and O-C(CH3)=O)
Plus ethanoic acid
What is the functional group? What two things add to form an eater and water? Word equation What do you do to the reactants? What is this known as? Equation with ethanoic acid and ethanol What is the name of the ester? What is the equilibrium mixture formed poured into? Does the ester miscible with water? What is used to separate the two?
RCOR Carboxylic acid and alcohol Carboxylic acid+alcohol>ester+water Reflux with strong acid CH3COOH+CH3CH2OH> CH3CH2OOCH2CH3+H2O Ethyl ethanoate Xs warm H2O No sits on top Separating funnel
