BMS1011 WK2L1 Part C flashcards

Aldehydes and Ketones Overview

• Aldehydes and ketones are important functional groups in organic chemistry.

• Aldehydes contain a carbonyl group (C=O) with at least one hydrogen atom (proton) adjacent to the carbonyl, while ketones have carbon atoms on both sides of the carbonyl group.

• Key Definitions:

  • Carbonyl Group: The functional group consisting of a carbon atom double-bonded to an oxygen atom.

  • Aldehyde: Contains a carbonyl group adjacent to a hydrogen atom.

  • Ketone: Contains a carbonyl group flanked by two carbon atoms.

Carboxylic Acids

• Carboxylic acids have a carbonyl group (C=O) and a hydroxyl group (–OH) directly attached to the same carbon atom.

• Important to note that this structure is a single functional group and should not be segmented into separate functional groups (e.g., ketone and alcohol).

• Properties of Carboxylic Acids:

  • Capable of extensive hydrogen bonding, leading to higher boiling points compared to alcohols.

  • They can form crystalline structures due to strong intermolecular forces.

  • Common example: Ethanoic acid (acetic acid) is a liquid and can form crystals easily.

Esters and Amides

• Esters: Formed from the reaction of a carboxylic acid with an alcohol. Their structure includes a carbonyl group bonded to an oxygen atom, which is also connected to another carbon atom.

  • Naming convention: Derived from the parent carboxylic acid and the alcohol used in the reaction (e.g., ethyl propanoate).

• Amides: Formed when a carboxylic acid reacts with an amine, resulting in a carbonyl group adjacent to a nitrogen atom.

  • In amides, the structural unit that includes the carbonyl and the nitrogen is considered the functional group, often involved in peptide bond formation between amino acids.

Oxidation Series

• The relationship between alcohols, aldehydes, and carboxylic acids follows an oxidation series:

  • Primary Alcohol → Aldehyde → Carboxylic Acid

  • The transformation involves the oxidation process where a C–H bond is replaced by a C=O bond.

  • Secondary Alcohol → Ketone

  • Tertiary alcohols cannot be oxidized as they lack a hydrogen atom on the carbon with the hydroxyl group.

Oxidation States in Organic Chemistry

• Organic chemistry often involves redox reactions where changes in oxidation states occur:

  • Increasing oxidation states correlate with the addition of C=O bonds and the loss of C–H bonds.

  • Mapping from primary alcohols (–1) to aldehydes (+1) to carboxylic acids (+3).

• In biochemical contexts: Reduction adds C–H bonds, while oxidation removes them, important for energy transformations.

Functional Group Relationships and Significance

• Understanding functional groups and their relationships is crucial in organic chemistry, not only for reactions but also for the synthesis of various compounds.

• Example: Morphine, heroin, and codeine all share a similar molecular skeleton but have distinct functional groups leading to differing biological activities, showcasing the significance of small structural differences.

Key Takeaways

• Aldehydes, ketones, carboxylic acids, esters, and amides are core functional groups that exhibit varied properties and reactivity in organic chemistry.

• The transformation of these groups illustrates broader concepts like oxidation and reduction, as well as the importance of understanding chemical structures in relation to function.