Lecture 1 Orgo

Front 1

ether

Back 1

R-O-R

Front 2

prefixes

Back 2

meth-
eth-
prop-
but-
pent-
hex-
hept-
oct-
non-
dec-

Front 3

n-propyl

Back 3

CH3-CH2-CH2-

Front 4

isopropyl

Back 4

CH3-CH-CH3
I

Front 5

n-butyl

Back 5

CH3-CH2-CH2-CH2-

Front 6

sec-butyl

Back 6

CH3-CH2-CH-
I
CH3

Front 7

isobutyl

Back 7

CH3-CH-CH3
I
CH2
I

Front 8

tert-butyl

Back 8

CH3
I
CH3 -- C -- CH3
I

Front 9

a bond is formed when...

Back 9

two electrons can LOWER THEIR ENERGY by positining themselves between two nuclei in such a way as to take advantage of the positive charge of both nuclei

Front 10

atoms that can form pi-bonds

Back 10

carbon
nitrogen
oxygen
sulfur

phosphorus with oxygen in ATP

3rd row elements form weaker pi-bonds than 2nd row elements

Front 11

to find type of hybrid orbital

Back 11

count number of sigma bonds and lone pairs of electrons on atom
match to the sum of the superscripts on hybrid name

Front 12

character or orbitals/bonding

Back 12

percentage of each type (s, p, d) a hybrid orbital is

sp2 is 33.3%s, 66.6%p

more s character, more stable, stronger and shorter

Front 13

sp bond angle

Back 13

180*
linear

Front 14

sp2 bond angle

Back 14

120*
trigonal planar

Front 15

sp3 bond angle

Back 15

109.5*
tetrahedral, pyramidal or bent

Front 16

dsp3

Back 16

90*, 120*
Trigonal-bypyramidal, seesaw, t-shaped, linear

Front 17

d2sp3

Back 17

90*
octhedral, square puramidal or square planar

Front 18

stability of resonance structures

Back 18

increases with more covalent bonds

decreases with separation of charges

Front 19

aromatic rings

Back 19

display resonance

planar, monocyclic rings with 4n+2 pi-electrons (Huckels rule)

Front 20

dipole moment

Back 20

when centre of positive charge on molec or bond does not coincide with the centre of negative charge

can occur in bond or molecule

induced dipole = weaker, from a nearby charge

instantaneous dipole = electrons moving (London dispersion forces; phase changes)

cause intermolecular attractions - proportional to their dipole moments

hydrogen bond is the strongest type

Front 21

isomers

Back 21

same molecular formula, but are different compounds

Front 22

conformers

Back 22

different spatial orientation of the same molecule

NOT true isomers

ie/ rotating around alpha-bonds; have different energy levels due to staggered and eclipsed conformations

Front 23

structural isomer

Back 23

same molecular formula, different bond-to-bond connectivity

iso-butane and n-butane

Front 24

chiral

Back 24

"handedness"

any C is chiral if bonded to 4 different substituents

describe by absolute configuration: R clockwise and S counterclockwise from highest to lowest priority
NOTE does NOT give info about rotating plane-polarized light

Front 25

relative configuration

Back 25

same chiral molec, but have ONE different substituent, and all others are identically orientated

Front 26

observed rotation

Back 26

direction and degree to which a compound rotates plane-polarized light

Front 27

polarimeter

Back 27

screens out photons with all but one direction of electric field - plane-polarized light

Front 28

optically inactive compounds

Back 28

either have no chiral centres OR racemic mixtures

Front 29

optically active mixtures

Back 29

when plane-polarized light is projected thru compound, orientation of its electric field is rotated

clockwise = + or d
counterclockwise = - or l
(nothing to do with chirality R and S...)

observed rotation = direction and number of degrees it rotates

specific rotation is standardized form w parameters (equal to observed after adjustments for length of polarimeter, soln concentration, temp, wavelength)

Front 30

stereoisomers

Back 30

same molecular formula and same bond-to-bond connectivity BUT not the same compound

enantiomers and diasteriomers

Front 31

enantiomers

Back 31

same molec formula
same bond-to-bond connect
MIRROR images
- opposite absolute config at every chiral C

Front 32

optical and enantiomeric purity

Back 32

equal for any mixture of enantiomers

optical is rotation of mix to rotation of pure sample

enant is rotation of mix to rotation of racemic mix

Front 33

diastereomers

Back 33

same molec formula
same bond-to-bond
NOT MIRROR images

geometric isomers
epimers/anomers

Front 34

geometric isomers

Back 34

due to hindered rotation around a double bond

cis and trans
(Z and E if multiple substituents; depending on highest priority subs)

cis have dipole moment = stonger intermolec forces = higher boiling points
BUT less symmetry so hard to form crystals and therefore lower melting point
ALSO higher heat of combustions if have steric hindrance

Front 35

max number of optically active isomers

Back 35

2^n where n is the number of chiral centres

Front 36

meso compounds

Back 36

have plane of symmetry

2 chiral centres that offset each other, creating optical inactivity

Front 37

epimers

Back 37

diastereomers that differ only at one chiral carbon

ring closure at epimeric C = anomers (2 diastereomers formed)

chiral carbon of anomer = anomeric carbon

Front 38

anomeric carbon

Back 38

chiral carbon of an anomer (a diastereomer formed when an epimer creates a ring)