Class One Flashcards
meth prefix
1
eth prefix
2
prop prefix
3
but prefix
4
cyclo prefix
comes infant of an all carbon containing ring
alcohol functional group
alkyl halide
thiol group
ether
epoxide functional group
phenol
aldehyde
ketone
hemiacetal
acetal group
cyanohydrin
amine
imine
enamine
carboxylic acid
acid halide (chloride)
acid anhydride
ester
lactone (ester in a ring)
amide
lactam
when is an organic molecule saturated
if it contains no pi bonds and no rings
when is an organic molecule unsaturated
if it has at least one pi bond or a ring
saturated compound formula
has 2n + 2 hydrogen atoms
(with n being the # of carbon atoms)
degree of unsaturation formula
(2n-2) - x / 2
n = # of Cs
x = Hs or halogen
rule for nitrogen in the degree of unsaturation formula
replace each N by 1 C and 1 H for the formula
hybridization for linear
sp
hybridization for trigonal planar
sp2
hybridization for tetrahedral
sp3
what is a carbocation
positively charged species with a positive charge on C
carbocations will always be..
sp2 hybridized with an empty p orbital
what is a carbanion
negatively charged species with a negative charge on C
2 ways that organic intermediates are stabilized
inductive and resonance effects
how do inductive effects work
stabilize charge through sigma bonds
how do resonance effects work
stabilize charge by delocalization through pi bonds
what substituent is always an electron-donating group
alkyl substituents
what group stabilizes carbocations
electron donating groups
what groups stabilize carbanions
electron withdrawing groups
what is a conjugated system
a system containing 3 or more atoms that each bear a p orbital
localized electrons
electrons that are confined to one orbital
delocalized electrons
electrons that interact with orbitals on adjacent atoms
are organic acids strong or weak
weak - they do not dissociate completely in solution
ranking of acidity
most → least
strong acids → sulfonic acids → carboxylic acids → phenols → alcohols + water → aldehydes/ketones → alkanes/alkenes/alkynes
inductive effects and distance
the closer the electron withdrawing group is to the acidic proton, the greater the stabilizing effect
electronegativity and inductive effect
the more electronegative a substituent is, the greater its inductive effect
3 factors that affect acid strength
electronegativity
resonance
induction
what is a nucleophile
have unshared electron pairs or pi bonds
usually have a negative charge
nucleophiles are also known as..
Lewis bases
as negative charge increases, nucleophilicity..
increases
as you go down a family, nucleophilicity..
increases
as you go left across a period, nucleophilicity..
increases
what is an electrophile
electron-deficient species
positive charge
electrophiles are also known as..
Lewis acids
relationship between nucleophiles & electrophiles
nucleophiles donate electrons to electrophiles
why are weak bases good leaving groups
their negative charge is stabilized due to their large size
e.g. halogens
what is ring strain
when bond angles between ring atoms deviate from their ideal angle
result from ring strain
weakened C-C bonds
increased reactivity
what compounds have a large degree of ring strain
cyclopropane and cyclobutane
what is a constitutional isomer
compounds that have the same molecular formula but have their atoms connected together differently
what is a conformational isomer
compounds that have the same molecular formula and atomic connectivity but differ by rotation about a sigma bond
what is a staggered conformation
a sigma bond on one carbon bisects. the angle formed by two sigma bonds on the adjacent carbon
what is an eclipsed conformation
a sigma bond on one carbon directly lines up with a sigma bond on an adjacent carbon
is staggered or eclipsed conformation more stable
staggered
why is staggered more stable than eclipsed conformation
in staggered, the sigma bonds are as far apart as possible
steric hindrance
which is more stable - gauche or anti
anti
what is a stereoisomer
molecules that have the same molecular formula and connectivity but differ from one another in the spatial arrangement of the atoms
what is a chiral molecule
a molecule that cannot be superimposed on its mirror image
what is an achiral molecule
a molecule that can be superimposed on its mirror image
a carbon can have a chiral center if..
it has 4 different substituents
first rule for assigning absolute configuration
priority of the substituents is given to the atom attached to the chiral center with the highest atomic number
isotopes and the first rule of absolute configuration
priority is given to the heaviest isotope
second rule for assigning absolute configuration
a multiple bond is counted as 2 single bonds for the atoms involved
third rule for assigning absolute configuration
molecule is rotated so that the lowest priority group points directly away from the viewer
absolute configuration of R
if the path from highest to lowest priority group traveled clockwise
absolute configuration of S
if the path from highest to lowest configuration travelled counterclockwise
what is an enantiomer
non-superimposable mirror images
non-identical mirror images
what makes a compound optically actice
a compound that rotates the plane of polarized light
dextrorotatory compound
a compound that rotates plane-polarized light clockwise
(+)
levorotatory compound
a compound that rotates plane-polarized light in the counterclockwise direction
(-)
what is specific rotation
the magnitude of rotation of plane-polarized light for any compound
enantiomers and optical activity
a pair of enantiomers will rotate plane-polarized light with equal magnitude, but opposite directions
what is a racemic mixture
a 50/50 mixture of enantiomers (rotation = 0)
what is a diastereomer
stereoisomers that are not enantiomers
(non-superimposable, non-mirror images)
diastereomers - specific rotations
there is no relationship between the specific rotations of diastereomers as there is for enantiomers
how to resolve a racemic mixture
by using an enantiomerically pure chiral probe (or resolving agent) that associates with the components of the racemic mixture through covalent or intermolecular forces
products of resolving a racemic mixture
diastereomers that are capable of separation fie to their different physical properties
what is an epimer
subclass of diastereomers that differ in their absolute configuration at a single chiral center
(only one stereocenter is inverted)
R and S vs D and L
R or S = absolute configuration
D or L = relative configuration
what is an anomer
epimers that form as a result of ring closure
what is a mess compound
when there is an internal plane of symmetry in a molecule that contains chiral centres
not optically active - optical activity is cancelled out by either side
what is a geometric isomer
diastereomers that differ in orientation of substituents around a ring or double bond
cis molecule
a molecule in which the two higher priority groups are on the same side
trans molecule
a molecule in which the two higher priority groups are on opposite sides of the ring
Z configuration
the 2 high priority groups are on the same side of the double bond
E configuration
2 high priority groups are on opposite sides of the double bond
rule of chiral centres
2^n chiral centres
what is a chiral centre
carbon atom with 4 non identical substituents
electric field lines exit from ___ charge and enter from ___ charge
exit from positive
enter to negative
what insulates axons from the surroundings
myelin sheath
squalene is a precursor to..
steroid hormones
resistivity is _____ to temperature
linearly proportional
R1C(O)OR2 skeleton
skeleton of an ester
X is used to present a..
stop codon
