enantiomers and diastomers Flashcards
what are enantiomers
they are chiral molecules that are non identical mirror images of each other. they have no plane of symmetry
nonsuperimposable
Achiral molecules are
superimposable
if a molecule has a plane of symmetry
it cannot exist as enantiomers
constitutional isomers
have the same atoms with different connectivity
stereoisomers
same connectivity, rearranged differently in space
conformation change
changes caused by bond rotation
configuration changes
changes that are caused by breaking bonds
conformation changes mean
molecules are intercovertible
stereogenic
carbon with 4 different group
racemic solution
contains stereoisomers in equal ratios
many chiral products
exist as one enantiomer
enantiomerically pure
the same enantiomer in a solution
do enantiomers have the same chemical properties?
yes
do enantiomers have the same physical properties?
yes*
they rotate plane polarised light in opposite and equal
plane polarised
a beam of light where the direction of vibration align parrerel
what are enantiomers known as
+ or - r or s
diastereomers are
non mirror image non identical non superimposable
cis
priority groups on the same side
trans
priority group on opposite sides
diastereomers can be
achiral
diastereomers have
different physical and chemical properties
calculate the number of stereoisomers
2 ^ n
calculate the number of diastereomers
2 ^n-1
meso compound
meso isomers are
. A meso compound is “superimposable” on its mirror image
non optically active compound
why are meso compound inactive optically?
Meso form is optically inactive because the molecules in meso form have a plane of symmetry due to which the optical rotations of upper and lower parts are equal and in the opposite direction which balanced internally and compound becomes optically inactive. This property is called internal compensation.
chiral molecules with no stereogenic centre
allene
it is atropisomers
the double bond will not rotate
=c=
chiral defination
asymmetric in such a way that the structure and its mirror image are not superimposable
stereogenic
consisting of a central atom and four distinguishable ligands such that the interchange of any two leads to a stereoisomer;
how to seperate enantiomers
create diastereoisomers
they have different physical properties which makes it easier to seperate
seperating enantiomers is called ?
resolution
seperating enantiomers is called ?
resolution
