3.2 Synthesis Flashcards
Fission
Process of bond breaking
Homolytic Fission (3 points)
- Results in the formation of two neutral radicals
- Occurs when each atom retains one electron from the sigma covalent bond and the bond breaks evenly
- Normally occurs when non-polar covalent bonds are broken
Heterolytic Fission (3 points)
- Results in the formation of two oppositely charged ions
- Occurs when one atom retains both electrons from the sigma covalent bond and the bond breaks unevenly
- Normally occurs when polar covalent bonds are broken
Single-Headed Arrow
Movement of a single electron
Double-Headed Arrow
Movement of an electron pair
Homolytic fission in terms of arrows
Two single-headed arrows starting at the middle of a covalent bond
Heterolytic fission in terms of arrows
One double-headed arrow starting at the middle of a covalent bond
Nucleophiles (3 points)
- Negatively charged ions or neutral molecules that are electron rich
- Attracted towards atoms with a partial or full positive charge
- Able to donate an electron pair to form a new covalent bond
Examples of Nucleophiles
Cl-, Br-, OH-, CN-, NH3 and H2O
Electrophiles (3 points)
- Positively charged ions or neutral molecules that are electron deficient
- Attracted towards atoms with a partial or full negative charge
- Able to accept an electron pair to form a new covalent bond
Examples of Electrophiles
H+, NO2+, SO3
Haloalkanes
Substituted alkanes in which one or more of the hydrogen atoms is replaced with a halogen atom
Monohaloalkanes (2 points)
- Contain one halogen atom
- Can be classified as primary, secondary or tertiary with number of alkyl groups
Alcohols
Substituted alkanes in which one or more of the hydrogen atoms is replaced with a hydroxyl functional group
Ethers
Substituted alkanes in which a hydrogen atom is replaced with an alkoxy functional group, -OR
SN1 Reactions
Nucleophilic substitution reaction with one species in the rate determining step and occurs in a minimum of two steps via a trigonal planar carbocation intermediate
SN2 Reactions
Nucleophilic substitution reaction with two species in the rate determining step and occurs in a single step via a single five-centred, trigonal bipyramidal transition state
Substitution
Atoms are added to a molecule by replacing atoms already present
Addition
Joining two or more molecules together to form a larger molecule
Elimination
When a small group of atoms breaks away from a larger molecule with the release of a small molecule
Condensation
The joining of molecules with the release of water as a product
Hydrolysis
The breakdown of a molecule by water
Neutralisation
When an acid and a base react to form water
Markovnikov’s Rule
States that when a hydrogen halide or water is added to an unsymmetrical alkene, the hydrogen atom becomes attached to the carbon with the most hydrogen atoms attached to it already.
Amines
Organic derivatives of ammonia in which one or more hydrogen atoms of ammonia has been replaced by an alkyl group
Reducing Agent Example
Lithium Aluminium Hydride
