Lecture 12 Flashcards
Why do Carboxylic acids have a higher level of oxidation than ketones and aldehydes?
Carbon in the functional group of a carboxylic acid is bonded to 3 hetroatoms.
What are hetroatoms?
Atoms which are not bonded to hydrogen or carbon.
What is an aliphatic acid?
COOH is bonded to an ALKYL groupCOOH is bonded to an ALKYL group.
What is an aromatic acid?
COOH is bonded to an ARYL group.
Describe the reactivity difference between an aliphatic and aromatic acid?
Similar
What are long chain monocarboxylic acids called?
FATTY ACIDS
What hybrizisation is the carbon and oxygen in the carbonyl?
Sp2 Hybridised.
What is the bond angle of carbon/ oxygen?
120o
In the carboxylic acid functional group which two groups are eclipised?
O-H and C=O
IUPAC- How do you name a carboxylic:
i) aliphatic
ii) aromatic
LONGEST carbon chain with functional group named with parent alkane. Remove “e” and ADD “oic acid.”
Eg: Methane to Methanoic Acid
Aromatic carboxylic acids are named after the parent compound.
Eg: Benzene to Benzoic acid.
Common Naming- How do you name a carboxylic acid?
End in “ic acid”.
Eg: Methanoic Acid = Formic Acid.
Often derived from Latin or Greek word indicating original source.
IUPAC- How do you name an ester?
FIRST name the alky from the ALCOHOL –yl.
SECOND name is the ACID (with the C=O) -oate.
Split compound between (Single bond Oxygen) and (Double bond Oxygen).
Chemically- 2 Reagents and 1 Condition for the oxidation of primary alcohol or aldehyde to a carboxylic acid.
Reagents- KMnO4 & K2Cr2O7
Condition- Under reflux.
Biologically- Reagents and Cofactor needed for the oxidation of primary alcohol or aldehyde to a carboxylic acid.
ADH (alcohol dehydrogenase) Alcohol to Aldehyde
ALDH (aldehyde dehydrogenase) Aldehyde to Carboxylic Acid
NAD+/ NADP+- Accepts H that is lost
2 Reagents for the oxidation of a substituted aromatic?
KMnO4 & K2Cr2O7
Carboxylic Acids via Hydrolysis- Esters- Chemically- Reagent?
Acid/ Base
In Hydrolysis creating carboxylic acids chemically what happens when a base reagent is used?
Carboxylic acid salt is produced and so needs to be treated with protonation to get the acid out.
Carboxylic Acids via Hydrolysis- Esters- Biologically- Reagent?
Esterases.
When Carboxylic acids are created by Hydrolysis what mechanism is involved with nitriles?
NUCLEOPHILC SUBSTITUITION
When Carboxylic acids are created by Hydrolysis what is the reagents?
First Stage- NaCN
Second Stage- H3O+
When Carboxylic Acids are created via Condensation what is the chemical reagent used?
Grignard Reagent-
When Carboxylic Acids are created via Condensation what is the mechanism in the first step of this reaction called?
NUCLEOPHILIC ADDITION
Describe the chemical reaction in creating a carboxylic acid via condensation.
- NUCLEOPHILIC ADDITION, the nucleophile is the C in the Carbon Dioxide.
- ORGANIC carboxylic acid is produced.
- Reagent is BASIC so forms a metal salt which needs to be treated with acid to get rid of the metal.
When Carboxylic Acids are created via Condensation what is the biological reagent used?
- Rubsico and Biotin Dependent Carboxylases (Co-factor).
Describe the solubility of carboxylic acids.
- Similar to alcohols.
- Low molecular weight- hydrogen bonds so can dissolve in water.
- Basic conditions- carboxylic acids present as a SALT so can dissolve in water through ion- dipole interactions.
- Larger carboxylic acids not soluble in water- more hydrophobic forces.