Test 3

Question 1

sigma is an

Answer 1

internal plane of symmetry

Question 2

define chiral

Answer 2

a carbon atom bonded to 4 DIFFERENT unique groups

Question 3

can atoms with double or triple bonds be chiral

Answer 3

NO

Question 4

chiral is to

Answer 4

directionality

Question 5

how do sigmas impact chirality

Answer 5

molecules with sigmas do NOT have chirality

Question 6

geminal

Answer 6

two functional groups bonded to the same carbon

Question 7

can a molecule be achiral but have chiral atoms

Answer 7

YES

Question 8

how to determine chiral atom on cyclic compounds

Answer 8

starting at carbon in question, move clockwise and then counterclockwise around the cyclic compound.
if you encounter the same pattern in both directions there is an internal plane of symmetry and it is ACHIRAL.
if the pattern is different, there is no internal plane of symmetry and it is CHIRAL.

Question 9

how to rank priority of atoms when determining directionality

Answer 9

higher atomic number = higher priority

Question 10

impact of the priority 4 atom

Answer 10

NOT NECESSARY for determining R or S configuration
priority 4 atom should be on a HASH

Question 11

the ________ the unbranched chain, the more important it is

Answer 11

LONGER

Question 12

tiebreaker protocol for same atoms when chains are UNBRANCHED

Answer 12

whichever atom is part of a longer (unbranched) chain is more important

Question 13

tiebreaker for chains when one or more is branched

Answer 13

add up protons of atoms directly connected to atom in question

Question 14

H should be on a

Answer 14

hash

Question 15

enantiomer

Answer 15

mirror image

Question 16

enantiomer of an R molecule is

Answer 16

S

Question 17

in order to draw an enantiomer there MUST be

Answer 17

at least one chiral carbon

Question 18

2 methods of drawing enantiomers

Answer 18

1) flip all wedges and hashes
2) draw mirror image

Question 19

ring flip method

Answer 19

left <-> right
wedge <-> hash

Question 20

diastereomers

Answer 20

non-superimposable
not mirror images

Question 21

meso compound

Answer 21

molecule has multiple chiral carbons but is NOT a chiral molecule

Question 22

D =

Answer 22

right handed

Question 23

L =

Answer 23

left handed

Question 24

the d,l pattern is

Answer 24

dextro, levo
2 chiral, no sigma
SS or RR

Question 25

the meso pattern is

Answer 25

internal mirror plane
2 chiral, 1 sigma
SR, RS

Question 26

chiral atoms are ______ active

Answer 26

optically

Question 27

2S, 3R-dibromobutane diastereomers

Answer 27

2R, 3R or 2S, 3S

Question 28

2S, 3R-dibromobutane enantiomer

Answer 28

2R, 3S

Question 29

R ring flip ->

Answer 29

R

Question 30

R mirror image ->

Answer 30

S

Question 31

R draw the enantiomer ->

Answer 31

S

Question 32

R Td rotation pinwheel ->

Answer 32

R

Question 33

are diastereomers or enantiomers more difficult to separate, why?

Answer 33

enantiomers
same boiling point, same polarity, etc

Question 34

Dextro- stands for ______. Dextro- is otherwise stated as ____. It refers to a molecule which _____________.

Answer 34

dextro-rota-tory
+
rotates light clockwise

Question 35

Levo- stands for ______. Levo- is otherwise stated as ____. It refers to a molecule which _____________.

Answer 35

rotates light counterclockwise

Question 36

drawing meso compounds

Answer 36

descending/ascending staircase format
wedge/wedge or hash/hash

Question 37

drawing d,l compounds

Answer 37

descending/ascending staircase format
wedge/hash or hash/wedge

Question 38

tetrahedral rotations

Answer 38

spin bottom 3
think pinwheel on stick

Question 39

how does a ring flip impact wedges and hashes

Answer 39

inverts them