Ch. 6

Question 1

Alkyl Halides are _____ leving groups and ______ nucleophiles with the exception of ______SN1

Answer 1

great
great
Fluorine

Question 2

Do vinyl halides do SN1, SN2, or neither

Answer 2

Neither

Question 3

Do aryl halides do Sn2, SN1 or neither

Answer 3

Neither

Question 4

Nomenclature (Halogens)

Answer 4

1. Find the longest carbon chain, even if the halogen is not bonded to any of those carbons

Question 5

Geminal dihalide

Answer 5

The two halogens are bonded to the same carbon

Question 6

Vicinal dihalide

Answer 6

The two halogens are bonded to adjacent carbons

Question 7

What two properties indicate higher boiling points

Answer 7

Greater mass, greater intermolecular forces

Question 8

Spherical shape ______ boiling point

Answer 8

decreases

Question 9

Which halogens are denser than water

Answer 9

Alkyl chlorides with two or more chlorines
Alkyl bromides
Alkyl iodides
(alkyl fluorides ARE NOT)

Question 10

When adding Br, remove the ______ CH

Answer 10

weakest

Question 11

Resonance stabilization of a radial makes it ______ to lose an H

Answer 11

easier

Question 12

A radical wants to be on a tertiary/secondary/primary carbon

Answer 12

tertiary

Question 13

Nucleophilic substitution

Answer 13

Halide leaving group is replaced by a nucleophile

Question 14

Elimination

Answer 14

Halide leaving group leaves and electrophile removes a H

Question 15

Nucleophilic substitution requires an _____ hybridized carbon

Answer 15

sp3

Question 16

A good leaving group has a ______ pKa of its conjugate acid

Answer 16

Low

Question 17

Common electrophiles

Answer 17

R-Cl, R-OH, R-OH2+, R-H, R-CH3

Question 18

Common leaving groups

Answer 18

Cl-, HO-, H2O, H-, CH3-

Question 19

Common nucleophiles/bases

Answer 19

Cl-, OH-, H2O, CH3-, NH2, NH3

Question 20

Polar Protic Solvents (Rank F- to I-)

Answer 20

Solvates I- best, then Br-, then Cl-, then F-

Question 21

Polar aprotic Solvents (Rank F- to I-)

Answer 21

Solvates F- best, then Cl-, then Br-, then I-

Question 22

Sn2 Rate Law

Answer 22

Rate = k[Nuc][Elect]

Question 23

SN2 performs a ________ attack

Answer 23

backside atack

Question 24

Backside Attack

Answer 24

the nucleophile attacks the electrophilic center on the side that is opposite to the leaving group; Inverts stereochemistry

Question 25

SN2 needs a _______ nucleophile/electrophile

Answer 25

good

Question 26

What degree of carbon is fastest with Sn2? Which degree doesn't react? How does steric impact speed

Answer 26

1º is faster than 2º 3º doesn't react More sterics, slower rate

Question 27

A negatively charged nucleophile is ________ that its neutral counterpart

Answer 27

stronger

Question 28

Nucleophilicty _____ from left to right

Answer 28

decreases`

Question 29

Nucleophilicity ______ down the periodic table as size and polarizability increase

Answer 29

increases

Question 30

What is the polarizability effect?

Answer 30

Bigger atoms are more polarizable and better nucleophiles than expected based on pKa alone

Question 31

SN1 Rate Law

Answer 31

Rate = k[Electrophile]

Question 32

Which reaction produces both stereoisomers

Answer 32

SN1

Question 33

Delete

Answer 33

3º > 2º > 1º > Methyl

Question 34

Polar protic solvnts are best for _____. Why?

Answer 34

SN1, solvates ions through hydrogen bonding

Question 35

Hammond Postulate

Answer 35

The transition state most closely resembles the starting material/product/intermediate that it is closest to in space

Question 36

SN1 can react with ____ nucleophiles, SN2 needs ____ nucleophiles

Answer 36

weak Strong

Question 37

Do Csp2-X halides react?

Answer 37

NO!

Question 38

What is a hydride shift? When can it occur?

Answer 38

Shift the H atom and 2 electrons in a bond, when it makes an equally or more stable carbocation

Question 39

How many carbons can you move over in a hydride shift?

Answer 39

One

Question 40

Which solvent doesnt have any H bonds

Answer 40

Polar Aprotie

Question 41

A good nucleophile is a _______ base

Answer 41

strong