L5 - carbon compounds and isomerism Flashcards
rank the functional groups from most to least polar
also solubility and b.p
amide> acid>alcohol>ketone/aldehyde> amine>ester>ether>alkane
define alkyl
alkane missing 1 H atom
usually attached to another molecule
how are alkyls named (eg meth)
methyl
define aryl
functional group derived from simple aromatic ring eg phenyl
what happens to lipid bilayer at low temps
gel phase
tightly packed
what happens to bilayer at high temps
fluid phase
loosely packed
when is E/Z nomenclature used
what is E
what is Z
for alkenes where every attached group is different
E - highest priority opposite
Z - highest priority same side
what is an alkyne
C-C with triple bond
what can affect membrane fluidity
length of FA chains
amount of C=C bonds
position of C=C bonds
cis/trans C=C bonds
what is the bonding in alkynes
1 sigma
2 pi
what are enantiomers
optical isomers
how does b.p differ between alkenes alkanes alkynes
similar, but alkenes slightly lower due to inability to tightly pack
describe steps of cahn ingold prelog (r/s) to determine enantiomers
- chiral C in middle, place lowest priority group (4) in the top left
- assign the remaining groups lowest to highest (1) priority in their positions around 4
- draw an arrow in the direction 1-2-3 (ignore 4
- if the arrow clockwise - R
if arrow anticlockwise - S
when determining R/S enantiomers , what does a clockwise arrow mean
R
when determining R/S enantiomers , what does an anti-clockwise arrow mean
S
what does laevorotary (L) (-) mean in relation to optical isomers
the optical isomer enantiomer that rotates plane polarised light to the left
what does dextrorotary (D) (+) mean in relation to optical isomers
the optical isomer enantiomer that rotates plane polarised light to the right
what is plane polarised light
light vibrations that occur on a single plane
what is the name given to enantiomer that rotates plane polarised light to the left?
laevorotary (L) (-)
what is the name given to enantiomer that rotates plane polarised light to the right?
dextrorotary (D) (+)
what is keto - enol isomerism
an equilibrium between ketone(or aldehyde) and enol form of a molecule
there is interconversion between the two
what are tautomer’s
the ketone(or aldehyde) form and enol form of a molecule (keto enol isomerism)
how can interconversion between keto - enol isomers be catalysed
by acid/base/enzymes
