Reactions and Mechanisms in Organic Chemistry Pt. 1
No description yet. This curated deck is ready for daily study.
Card preview (24)
Define chirality
Chiral molecules are molecules which are non-superimposable mirror images of each other
what is required for chirality in molecules and why is it important
• to have chirality a molecule must have a chiral centre, this is often a carbon attached to 4 different groups • Enantiomers (pairs of chiral molecules) are mirror images but do not necessarily have the same properties
how are bonds out of plane, bonds into plane and partial bonds represented
bonds out of plane of paper = wedge bond into plane of paper = hashed partial bond = dashed
why are C-C or C-H bonds not very reactive
• they have a high bond enthalpy and are not strongly polarised
why are C-X bonds more reactive and in what way are they generally reactive
• usually polarised and reactive towards nucleophilic attack • generally the carbon is attacked as it is delta +ve • they are much easier to break in a chemical reaction
what is the difference between primary, secondary and tertiary alcohols, give the names for the propane type alcohols for each
primary = -OH attached to a carbon that’s attached to 1 carbon e.g. propan-1-ol secondary = -OH attached to a carbon that’s attached to 2 carbons e.g., propan-2-ol tertiary = -OH attached to a carbon that’s attached to 3 carbons e.g. 2 methyl, propan-2-ol, or tert-butanol
what is an ether and what is something to note about them
the functional group of R1-O-R2 R1 does not have to be the same as R2 e.g. tert-butyl methyl ether
what is an amine and what the difference between primary, secondary, tertiary
amine is the R(x+1)-NH(2-x) x < 3 • the terms primary/secondary/tertiary refer to the number of hydrogens on the ammonia which have been replaced • a primary amine is where one hydrogen on the ammonia has been replaced • a secondary amine is where 2 hydrogens have been replaced • a tertiary amine is where 3 hydrogens have been replaced
what is an amine and what the difference between primary, secondary, tertiary
amine is the R(x+1)-NH(2-x) x < 3 • the terms primary/secondary/tertiary refer to the number of hydrogens on the ammonia which have been replaced • a primary amine is where one hydrogen on the ammonia has been replaced • a secondary amine is where 2 hydrogens have been replaced • a tertiary amine is where 3 hydrogens have been replaced
what is the functional group of halides
molecules with the functional group of R-X where X is any one of the halogens, F,Cl,Br,I
what are generally considered carbonyl group derivatives
• aldehydes, ketones, carboxylic acids, esters, amides and acid halides
difference between alkene and alkyne
alkene = C=C double bond alkyne = C=_C triple bond
what is an aldehyde and what is a ketone
• an aldehyde is where a hydrogen is attached to the carbon of the carbonyl bond i.e. R-CHO • a Ketone is where the carbon of a carbonyl bond is not terminal i.e. RCOR
what is a carboxylic acid and what is an acid halide
• a molecule containing the functional group RCOOH • an acid halide is a molecule containing the functional group RCOX where X is one of the halides (C is terminal)
what is an ester, how do we name them
a molecule containing the functional group R(1)COOR(2) Note R(1) and R(2) do not have to be the same to name do alkyl alkyloate e.g. methyl ethanoate this would be where R(1) is ethane based and R(2) is methane based
what is an acid anhydride
R(1)COOCOR(2) Note: R(1) and R(2) do not have to be the same but usually are
what is an amide
a molecule containing the group RCONH2 = primary amide RCONHR(1) = secondary amide RCONR(1)R(2) = tertiary amide
what is a nitrile
a molecule containing the functional group R-C=_N (triple bond)
what is retrosynthetic analysis and what type of arrow do we used to represent ‘can be made from’
• it’s a process where we look at the target molecule and ask ‘How can I make this’ • we use a fat arrow
what must two or more orbitals be in order to interact
• close in energy • overlap efficiently • be of suitable symmetry
what things must we consider when analysing molecular interactions (usually with HAOs)
primarily: - HOMO/LUMO interactions - electrostatic interactions related: - hardness and softness and hence, whether a reaction is FMO or electrostatics driven - orbital coefficients - symmetry
what is the important thing to consider when deciding which HOMO/LUMO interaction is most effective
• relative, not absolute energy levels are important • this means the interaction with the lowest difference in energy between the HOMO of the nucleophile and LUMO of electrophile is the most effective
what is a curly arrow and where is it used, what are the different types
• curly arrows represent the movement of a single or pair of electrons from a filled orbital (HOMO) to an empty orbital (LUMO) • the arrow starts with its tail on the source of the moving electrons representing the HOMO • it finishes with the head of the arrow pointing close to the empty orbital (LUMO) • a double headed arrow represents a pair of electrons • a single headed arrow represents a single electron
what is a nucleophile
• an electron pair donor