Umaine Organic Chemistry Exam 2 – Flashcards
Unlock all answers in this set
Unlock answersquestion
alkane
answer
hydrocarbons that lack pi bonds
question
how to name alkanes
answer
1. identify parent compund 2. name substituents 3. number the carbon atoms and assign a locant to each substituent 4. assemble substituents alphabetically.
question
propyl
answer
3 carbon atoms
question
butyl
answer
4 carbon atoms
question
pentyl
answer
5 carbon atoms
question
naming bicyclic compounds
answer
1. identify bicyclo parent, indicate bridgeheads 2. identify and name substituents 3. # parent chain (start with longest bridge) and assign locant to each subsitituent 4. assemble substituents alphabetically
question
staggered newman projection
answer
-more stable (favored) -lower energy
question
eclipsed newman projection
answer
-less stable -higher energy
question
anti conformation
answer
-more stable -lower energy
question
gauche conformation
answer
-less stable
question
chair conformation stability
answer
equitorial position is favored, has lower energy
question
cis-trans stereoisomerism
answer
cis- same side of ring trans- opposite sides of ring
question
stereoisomer
answer
same formula and constitution, different spatial arrangement of atoms
question
superimposable
answer
mirror image is identical to the object (achiral)
question
chiral
answer
objects that are not superimposable
question
chirality center
answer
tetrahedral carbon bearing 4 different groups
question
enantiomers
answer
when a compound with one chirality center has one superimposable mirror image
question
assigning configuration (R&S)
answer
1. identify 4 atoms attached to chirality center and prioritize by atomic # 2. rotate molecule so that the 4th priority is on a dash 3. identify direction of 1-2-3 sequence, clockwise=R, counterclockwise=S
question
optically pure
answer
a solution containing a single enantiomer
question
racemic mixture
answer
-a solution with equal amounts of both enantiomers -optically inactive
question
diastereomers
answer
stereoisomers that are not mirror images
question
max # of stereoisomers
answer
2^n where n= # of chirality centers
question
rotational symmetry
answer
-has an axis of symmetry -rotates 180 degrees -chirality is not dependent on it
question
reflectional symmetry
answer
-has a plane of symmetry -a compound that possesses a plane of symmetry is achiral
question
meso compound
answer
contains chirality centers but is achiral because it possesses reflectional symmetry
question
fischer projections
answer
-vertical lines are dashes (go behind the page) -horizontal lines are wedges (come out of the page)
