Chp. 11-13 Exam Review Flashcards Preview

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Flashcards in Chp. 11-13 Exam Review Deck (38)
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1

What do you get when you oxidize secondary alcohol with PCC?

Ketone

2

What is Markovnikov's Rule?

* "The rich get richer"

* The carbon with the largest # of carbon atoms gets the X (halogen) or OH bind to it

3

What is conjugation?

Sequence of alternating double or triple bonds.

4

What are 5 common nucleophiles?

I-

Br-

Cl-

HS-

H2S

RSH

HO-

RO-

NC-

5

What happens when secondary alcohol undergoes... a) KMnO4 b) H2CrO4 c) PCC

The secondary alcohol is converted to... a) Ketone b) Ketone c) Ketone

6

What is oxidation?

1. Loss of electrons; 2. Adding an oxygen; 3. Adding an additional bond to the oxygen (eg. from single bonded oxygen, it becomes double bonded)

7

What are the names of the molecules from left to right?

Ketone; aldehyde; carbocyclic acid

8

What reagent can you use to convert an alkene to an epoxide?

MCPBA

9

What is chromic acid?

H2CrO4

10

What reagents can you use to reduce a ketone to a 2* alcohol?

NaBH4 or LAH

11

What product do you get when you apply PCC on a 1* alcohol?

Aldehyde

12

Are the following acids strong or weak? What are their pkas?

I-H

Br-H

Cl-H

SO3-H

HO3+

These are strong acids. Their pkas are...

I-H     -11

Br-H     -9

Cl-H     -7

SO3-H     -3

HO3+     -2

13

What product do you get?

14

What is this molecule?

Benzene

15

What do you get when you oxidize a 1* alcohol with H2CrO4?

Carboxylic Acid 

16

What does aprotic mean?

The solvent does NOT have a proton on an electronegative atom.

17

Are the following acids strong or weak? What are their pkas?

H20

1* alcohol

3* alcohol

NH3

These are weak acids. Their pkas are...

 

H20              15.7

1* alcohol       16

3* alcohol      18

NH3                38

18

If the top row is a reactant, and the bottom row is the product, is this oxidation or reduction? Why?

Reduction. You are adding an H. (Gained electrons)

19

What is the product if you use KMnO4, H2CrO4 or PCC with tertiary alcohol?

No Reaction

20

What do you get when you oxidize primary alcohol with KMnO4?

Carboxylic Acid

21

What product do you get if you reduce a carboxylic acid with NaBH4?

No Reaction

22

What happens when primary alcohol undergoes... a) KMnO4 b) H2CrO4 c) PCC

The primary alcohol is converted to... a) Carboxylic acid b) Carboxylic acid c) Aldehyde

23

Examples of polar aprotic solvents.

acetone, DMSO, DME and DMF

24

When primary alcohol undergoes PCC, what happens?

It becomes an aldehyde.

25

What are examples of reducing agents?

1) LiAlH4 (LAH);

2) NaBH4, H20;

3) H2, Ni;

4) Na, EtOH

26

Is this oxidation or reduction?

What are the reagents to get the products from top to bottom?

This is oxidation.

KMnO4

H2CrO4

PCC 

27

What is a reduction?

Gain of electrons.

28

What three reagents can you use to convert a 2* alcohol to a ketone?

KMnO4 and H2CrO4 and PCC

29

Does strong Acid have a weak conjugate base?

True

30

What happens when tertiary alcohol undergoes... a) KMnO4 b) H2CrO4 c) PCC

What happens when tertiary alcohol undergoes... a) No reaction b) No reaction c) No reaction

31

What do you get when you reduce a carboxylic acid with LAH? How about with NaBH4?

1* alcohol; No Reaction

32

What is the product from top to bottom?

33

What mechanism is this? You have a tertiary, nucleophile, leaving group and a polar solven to stabilize the carbocation.

SN1

34

This mechanism works for primary, maybe secondary; you need a strong nucleophile and leaving group; there is an inversion at the chirality center, need  a polar solvent to dissolve nucleophile and it is favored by polar aprotic solvents.

SN2

35

What is Hoffman Rule

* Elimination yields the least substituted alkene

* use a bulky base such as tert-butoxide (t-BuOK) in tert-butyl alcohol (t-buOH).

36

* Favors substrates that can form stable carbocations.

* Bulky group

*Alcohols dehydrated follows this mechanism in 2* and 3* alcohols

* Favored by use of POOR NUCLEOPHILES (weak bases) 

E1

37

* Uses a 2* or 3* alkyl halide is possible;

* HIgh temperature favors elimination over substitution

* Use EtONA/EtOH and t-BuOK/t-BuOH

Zaitsev product

* Primary alcohols follow this mechanism or rearrangement

* H must be anti to leaving group

E2

38