week 2 - functional groups and chirality

Cards (30)

  • drawing molecules
    • structural formula = lewis
    • skeletal formula = line
    • semi structural = condensed
    A) line
    B) lewis
    C) condensed
  • types of carbon atoms
    • Primary: a carbon bonded to 1 other carbon
    • Secondary : a carbon bonded to 2 other carbons
    • Tertiary: a carbon bonded to 3 other carbons
    • Quaternary: a carbon bonded to 4 other carbons
    A) quarternary
    B) primary
    C) secondary
    D) tertiary
  • functional group definition
    • “An atom or group of atoms within a molecule that shows a characteristic set of physical and chemical properties”
  • types of functional groups
    A) ether
    B) aldehyde
    C) ketone
    D) imine
    E) nitrile
    F) thiol
    G) azo
  • alkane
    • saturated hydrocarbons
    • shape: tetrahedral carbon, all bond angles are ~109.5
  • alkene
    • unsaturated hydrocarbon
    • shape: trigonal planar at carbon, all bond angles are ~120
  • naming compounds
    • prefix: tells us number of C's in parent chain
    • infix: tells us nature of carbon-carbon bonds
    • suffix: tell us class of compound (ie. functional group)
    A) infix
  • dipole dipole interactions
    • the attraction between the positive end of one dipole and the negative end of another dipole
    • ie. slightly negative --- slightly positive
  • amines
    • Primary: a nitrogen bonded to only 1 other carbon
    • Secondary: a nitrogen bonded to 2 other carbons
    • Tertiary: a nitrogen bonded to 3 other carbons
    • Quaternary a nitrogen bonded to 4 other carbons
    A) quarternary
  • functional group conversions
    • primary alcohol -> aldehyde -> carboxylic acid
    • secondary alcohol -> ketone
    • tertiary alcohol
  • alcohols
    • primary: the OH is bonded to one carbon atom
    • secondary: the OH is bonded to 2 carbon atoms
    • tertiary:the OH is bonded to 3 carbon atoms
  • cool
    • the difference between morphine, heroin and codeine is the functional groups attached to them
    A) acetate
  • isomers
    • same molecular formula but different arrangement in space
    constitutional isomers (ie. structural isomer)
    • same molecular formula but different skeleton of molecule (eg. butane to methyl propane)
    stereo isomers
    • same molecular formula but have different 3D orientation in space
    • geometric (cis/trans) and optical (enantiomers/diastereomers)
  • isomers
    • same molecular formula but different arrangement in space
    constitutional isomers (ie. structural isomer)
    • same molecular formula but different skeleton of molecule (eg. butane to methyl propane)
    stereo isomers
    • same molecular formula but have different 3D orientation in space
    • geometric (cis/trans) and optical (enantiomers/diastereomers)
    A) constitutional
    B) diastereomers
    C) enantiomers
  • geometric isomers
    • they have a fixed orientation (ie. no rotation around the C=C)

    E and Z isomers
    • more specific than cis/trans
    • priority rule (CIP) : depends on the atomic number of the atom
    1. highest atomic number = highest priority
  • geometric isomers
    • they have a fixed orientation (ie. no rotation around the C=C)
    E and Z isomers
    • more specific than cis/trans
    • priority rule (CIP) : depends on the atomic number of the atom
    1. look at the 2 groups on each C atom SEPARATELY
    2. if the group is not one atom, but many, follow the chain one by one
    3. highest atomic number = highest priority
    4. if the highest priority groups are opposite, it is E
    5. if the highest priority groups are same side, it is Z
    A) cis
    B) trans
    C) Z
    D) E
    E) Z
    F) E
  • chirality
    • if a molecule is identical to its reflection, it is achiral
    • if a molecule is not identical to its reflection, it is chiral
    • eg. hands are chiral since its reflection is not identical to the original (ie. its mirror image is non-superimposable)
    A) chiral
    B) achiral
  • chirality
    • if a C has 4 different groups attached to it, it has a stereogenic centre, thus the molecule will most likely be chiral
    • enantiomer = a pair of chiral molecules
    • Enantiomers do not differ in physical characteristics, but interact differently with plane polarized light
    A) stereogenic
  • achiral
    • has a plane of symmetry
    • an object and its mirror image are superimposable
  • naming enantiomers
    1. locate the chiral/stereogenic centre
    2. assign priority 1-4 based on highest atomic number (if same, then go to next atom connected to it)
    3. orient the lowest priority group points away from you (usually H) and the other 3 groups towards you
    4. reading from group 1-3, if the order is clockwise (R - sinisiter - right) if the order is anticlockwise (S - sinister - left)
    A) R
    B) S
  • enantiomers...
    A) 256
  • Stereoisomers
    • R will always invert to S
    • S will always invert to R
  • diastereoisomers
    • stereoisomers that are not mirror images of each other (ie. cannot be superimposed)
    • not a pair of enantiomers
  • enantiomer
    • when all chiral centres change and there is a lack of symmetry
    mesoisomer
    • when all chiral centres change and there is a line of symmetry
    diastereoisomer
    • when some chiral centres change but not all
  • enantiomers and biology
    • enzymes can distinguish between their enantiomers
    • this is because the enantiomer's binding site will not fit the enzyme's active site
  • reminder
    A) away
    B) towards
    C) plane
  • the only exception to the 2^n rule
    • mesoisomers
  • stereoisomers summary
    • should be 2^2=4 stereoisomers, but due to meso, there's 3 stereoisomers
    • 1 & 2/4 are diastereoisomers (not mirror images)
    • 1 & 3 are mesoisomers (symmetry plane)
    • 2 & 3 are diastereoisomers (not mirror images)
    • 2 & 4 are enantiomers (mirror images)
    • 3 & 4 are diastereoisomers
  • table
    A) non-superimposable
    B) non-superimposable
    C) yes
    D) no
    E) superimposable
    F) mirror image
  • enantiomers
    • if their R and S configuration is exact opposite
    • eg. R&S enantiomer = S&R