Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Org Chem 1 > Exam 2 > Flashcards

Exam 2 Flashcards

1
Q

What is an alkane?

A

It is a saturated hydrocarbon (molecule with hydrogens and carbons)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What does saturated mean? Unsaturated?

A

Saturated means that there are as many hydrogens as possible. Unsaturated means that there are double or triple bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a homolog?

A

Compounds that only differ in the number of CH2 groups (root name)
methane, ethane, propane, butane, pentane, hexane, heptane, octane, nonane, decane, undecane, dodecane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the IUPAC naming for alkanes?

A

1) Find main chain (longest chain)
2) Number main chain from side with closes substituent
3) Name substituents as alkyl groups and give location (2-methyl not methane)
4) When 2+ alkyl groups put together alphabetically and when 2+ same alkyl groups combine numbers with commas and use di, tri, tetra, penta, hexa, hepta, octa, nona, deca, (2,2-dimethyl)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What about when two chains are the longest?

A

The chain with the most substituents wins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the rules for commas and dashes?

A

Numbers are separated by commas numbers and words separated by dashes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the common group names?

A

Isoalkyl
n-alkyl (normal don’t need to use n)
sec-alkyl (R group attaches to second)
tert-butyl (three carbons attached to central C)
R-CH3: Primary Carbon 1*
R-CH2-R: Secondary Carbon 2*
R-CH-R-R: Tertiary Carbon 3*
R-R-C-R-R Quatinary C 4*

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the complex naming of subsituents?

A

1) Find Main Chain
2) Number chain starting with C attached to backbone
3) Everything else the same

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the rules for cyclo compounds?

A

Root: either longest chain or biggest ring (whichever more C)
Don’t include ring in chain
Numbering the ring: start with two substituent over one, then start w/ alphabetically first, then go around to closest substituent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What prefixes count for alphabetical? Which don’t and why?

A

Count: Iso and cyclo
Don’t: sec-, turt-, cis-, trans- because has to do with spacial orientation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How does the root name change from alkanes to alkenes or alkynes?

A

Alkene: change to location-howmanyene
Alkyne: change to location-howmanyyne
Both: change to location-howmanyen-location-howmanyyne
Location = X where ene/yne starts
howmany = di, tri, etc
hept-1,3,5-triene
cis-oct-2-en-4-yne

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

When can cis/trans be used?

A

With double bonds and cyclo groups

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the parts of the name of alkenes/alkynes containing molecules?

A

1) Root
2) Suffix- establish this first as it dictates what the root is
3) Prefix- everything else falls in here

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the rules of more complicated organic molecules?

A

1) Identify highest priority functional group this is the suffix -all other groups will be substituents and included in the prefix
2) Identify the longest chain that contains the highest priority functional group -drop e of root if suffice starts with a vowel -longest chain with more substituents wins
3) Ennumeration: Highest priority group gets lowest number possible
-if tie give earliest substituent lowest number possible, if still tie go to the second substituent
-if still tie give lowest number to the substituent that comes first in the alphabet
4) Alkenes / ynes root ending changes to -ene or -yne
5) Prefix: list all remaining substituents in alphabetical orders
prefix, root name, and suffix without spaces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What happens with a nitrile?

A

the Carbon in the nitrile is number 1 of the longest chain when it is the highest priority

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the functional groups by priority?

A

Carboxylic acid, ester, amide, nitrile, aldehyde, ketone, alcohol, thiol, amine, alkene, alkyne, alkane, ether, halide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the suffix and prefix for carboxylic acid?

A

-oic acid and carboxy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the suffix and prefix for ester?

A

-oate and alkoxycarbonyl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the suffix and prefix for amide?

A

-amide and amido

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the suffix and prefix for nitrile?

A

-nitrile and cyano

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the suffix and prefix for aldehyde?

A

-al and formyl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the suffix and prefix for ketone?

A

-one and oxo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the suffix and prefix for alcohol?

A

-ol and hydroxy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the suffix and prefix for thiol (R-SH)?

A

-thiol and mercapto

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is the suffix and prefix for amine?

A

-amine and amino

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the suffix and prefix for alkene?

A

-ene and alkenyl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the suffix and prefix for alkyne?

A

-yne and alkynyl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the suffix and prefix for alkane?

A

-ane and alkyl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the suffix and prefix for ether?

A

There is no suffix and alkoxy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is the suffix and prefix for halide?

A

no suffix and halo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the complex naming of nitrile exception?

A

You do not have to put “1” if the nitrile is the base group because the C will ALWAYS be 1 in this case.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

How do you name bicyclos?

A

1) Count the carbons
2) Name it bicyclo[…]alkane (how ever many carbons)
3) Locate the two bridge head atoms (atoms where everything is connected)
4) Count how many carbons are needed to cross the bridge (always three numbers, if no carbons in between the answer is 0)
List largest to smallest [#.#.#]
bicyclo[2.2.1]heptane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

How do you name spiro compounds?

A

1) Count the carbons
2) Name is spiro[…]alkane (however many carbons name)
3) Count # of carbons on each loop (not combining carbon) and list smallest to largest [#.#]
spiro[2.5]octane

34
Q

When may cis/trans be used (as of now)?

A

One double bond (cannot rotate) cis-but-2-ene, trans-but-2-ene
Two comparable substituents on a ring cis-1,3-dimethyl cyclohexane
three substituents cannot be cis-trans

35
Q

What are the properties of methane?

A

Tetrahedral, sp3, 109.5* gas that burns in presence of oxygen

36
Q

How is ethane different from methane?

A

Two carbons joined by a single bond that is rotatable begging the question what is the most stable form/

37
Q

What is the most stable form of ethane?

A

When the hydrogens are not aligned giving the hydrogens more physical space

38
Q

What model is used to look a sigma bond head on?

A

Newman projection: spokes are the front and the circle is the back

39
Q

What is a confirmational analysis? What are the names of the stages?

A

A look at the energy for each 60* turn of a Newman Projection and plot
eclipsed, total eclipsed: highest energy
staggered: Gauche & anti - lowest energy (zigzag formation)

40
Q

What is saw horse projection?

A

looking a the bond at an angle

41
Q

What is the bond and stability of cyclopropane?

A

60*, not incredibly stable due to significant (109.5-60) angle strain and torsional strain (H’s are head on)
(angle + torsional = ring)

42
Q

What is the angle and strain of cyclobromane?

A

88, not 90 because skewed (bird) to relieve some torsional strain

43
Q

What is the angle and strain of cyclopentane?

A

108* envelope shape, little strain

44
Q

What is the angle and strain of cyclohexane?

A

109.5* chair (lower) and boat (higher) conformation, skewed boat in between.

45
Q

What are the names of the orientations of groups that come off of a cyclohexane?

A

Axial: straight up/down
Equatorial: out on side

46
Q

Where do bulky groups tend to orientate on cyclohexane?

A

Equatorial orientation.

47
Q

What compound must remain equatorial?

A

tert-butyl

48
Q

What is a mechanism?

A

A step-by-step of how a reaction happens, that is, where the electrons are moving, bonds broken and formed, as described by arrows single barbed arrow

49
Q

How can a cyclohexane model keep you from making a mirror mistake?

A

It can keep you from making the molecule’s enantiomer

50
Q

What is thermodynamics?

A

The study of energy changes that accompany chemical and physical transformations. Allows for the comparison of stability of reactants and products, which compounds favored by equilibrium

51
Q

What is kinetics?

A

Study of reaction rates, determining which products are formed fastest. Helps to predict how rate will change if change reaction conditions.

52
Q

What type of a mechanism is halogenation?

A

Free radical mechanism

53
Q

What is a free radical?

A

An unpaired electron

54
Q

What are the steps of a free radical mechanism? What must you remember for the exam?

A

Initiation, propagation, and termination
-do not have to label steps
-initiation, propagation (all steps to show propagation), and termination (one termination) must be drawn
-MUST HAVE ARROWS

55
Q

What happens to a mechanism when you add one chlorine or bromine?

A

Two propagation steps are added
1-2
3-6 etc

56
Q

What happens in the initiation step?

A

Two radicals come from none.
When light is applied a small fraction of bond between diatomic chlorine is broken leaving with two chlorine radicals. (Homolytic cleavage)

57
Q

What is the difference between homolytic and heterolytic cleavage?

A

Homolytic cleavage, also called radical cleavage, forms free radicals
Heterolytic cleavage, also called ionic cleavage, forms ions

58
Q

What occurs in the propagation step?

A

Halogen radical finds easiest partner H creating alkyl radical that must cleave halogen bond the halogen radical feeds back, propagates, to first reaction
not finished into all products are made

59
Q

What occurs in the termination step?

A

radicals come together
(or collision with side of glass causes impromptu reaction)

60
Q

What is the focus of thermodynamics in organic chemistry?

A

State functions and spontaneity
-Gibbs free energy must be negative for spontaneity
AG = AH - TAS
TAS soo small, essentially ignore
AG ~~AH
enthalpy will give a good idea of what is going on

61
Q

What is the formula for change in enthalpy?

A

AH = sum of (bond dissociation energy of broken) - sum of (bond dissociation energy of formed)

62
Q

What keeps spontaneous reactions from occuring?

A

Activation energy

63
Q

How is the rate of reaction determined?

A

Experimentally

64
Q

What is the transition state?

A

The highest point of energy, where bonds are being formed

65
Q

What is in a reaction energy diagram?

A

Reactants, activation energy leading to transition state, intermediates and products

66
Q

What must be included in an energy diagram?

A

Reactants, intermediates, products, change in enthalpy of each step and overall, activation energy of each step, transition state of each step (double dagger), rate determining step, and axis labels

67
Q

What is important to remember about RDS?

A

IT is the highest point on graph, pay attention to energy level with respect to starting materials

68
Q

What are the radical selectivity trends?

A

Most –> Resonance, tertiary, secondary, primary, Methyl –> least stable
Lowest intermediate energy: higher stability

69
Q

What is Hammond’s Postulate?

A

Related species that are closer in energy are closer in structure.

70
Q

How does Hammond’s Postulate apply to exothermic reactions?

A

The transition states are closer in energy to reactants so it is easier for them to go back to reactants. This means that there will be more reactants and the reaction will be less selective.
this is why we do not use fluorine, it is too exothermic and does not distinguish between forms

71
Q

How does Hammond’s Postulate apply to endothermic reactions?

A

The transition states are closer in energy to intermediates so it is easier for them to go forward to intermediates. This means that there will be less reactants and the reaction will be more selective.
this is why iodine does not work–it is too endothermic

72
Q

What are reactive intermediates?

A

Short-lived, “stable” species on way to products
carbocation, radical, carbanion, carbean

73
Q

What is a carbocation?

A

R3C+, sp2, electron poor so wants electron density through inductive effect

74
Q

What is the inductive effect?

A

The ability to share electrons through sigma bonds. Gets helping hand from near by Carbons if electron poor
C-C bonds are more electron rich than C-H bonds

75
Q

What is the range of stability for carbocations?

A

H3C+ < RC+H2 «< R2C+H < R3C+ < Resonance
Never form H3C + or RCH2+ without resonance

76
Q

What is a carbon radical?

A

R3C* electron poor because not full octet, sp2,
-radical in p orbital
-not as electron poor as carbocation so not as much stabilization needed (H3C, RCH2 possible)

77
Q

What is the range of stability for carbon radicals?

A

H3C* < RCH2 < R2CH < R3C* < resonance

78
Q

What about the central atom when there are radicals?

A

The central atom will never have the radical because there must always be a double bond

79
Q

What is a carbanion?

A

R3C- sp3 generally but if resonance sp2
electron rich so does not want more C around it

80
Q

What is the range of stability for carbanions?

A

Opposite of carbocations and radicals except for resonance wins
R3C- < R2C-H < RC-H2 < H3C- < resonance

Org Chem 1 (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions