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Question 1

why does OH need to be converted in order to do substitution or elimination chemistry?

Answer 1

it is a poor leaving group (strongly basic)

Question 2

if you have a tertiary alcohol, how can you make it a good LG?

Answer 2

with HCl or HBr, it proceeda through an SN1 mechanism with a carbocation and possible rearrangements

Question 3

when reacting HCl with a tertiary alcohol, what acid are you actually reacting with in the solution

Answer 3

h30

Question 4

what type of a reaction is PBr3? What does it react best with and what is the stereochemistry?

Answer 4

it is an SN2 like mechanism that proceeds with an inversion of stereochemistry. It

Question 5

what is the order of reactivity for PBr3

Answer 5

1>2>3

Question 6

what is the side product of PBr3 and alcohol reaction

Answer 6

OHPBr2

Question 7

what does SOCl2 react best with

Answer 7

it reacts best with 2° and 1° as it undergoes an SN2 mechanism

Question 8

what do we promote the SOcl2 reaction with?

Answer 8

we promote it with pyridine which deprotonates the OH

Question 9

what are the best leaving groups

Answer 9

Tosylate and Mesylate

Question 10

why is tosylate a good leaving group

Answer 10

it is lower in energy due to the negative charge on the oxygen and the ability for the molecule to be resonance stabilized in the carbonyl and the aromatic ring

Question 11

what happens to the stereochemistry of a chiral carbon when reacting with TsCl

Answer 11

the stereochemistry remains the same since the oxygen is the reactive site in the mechanism

Question 12

what are the limitations of an intermolecular dehydration

Answer 12

it is only good for symmetrical ethers, otherwise it creates mixed products and it can only occur in 140°C

Question 13

what happens when you react an alcohol with 180°C and H2SO4?

Answer 13

elimination will occur

Question 14

if you want to synthesize an unsymmetrical ether, what should you use?

Answer 14

Williamson ether synthesis, you want to formulate an alkoxide ion that will react with a primary alkyl halide

Question 15

how can alkoxide ions be generated

Answer 15

they are generated in situ and need to be deprotonated by a very strong base

Question 16

what inidcates that a william ether synthesis is occuring

Answer 16

H2 gas bubbling off in solution

Question 17

what are the results of an alkoxymercuration demurcuration

Answer 17

the addition of an ether to an alkene with markovnikov addition

Question 18

if you have an alchohol and a functional group present on the molecule, what do you need to add so the alcohol does not participate in acid-base chemistry

Answer 18

you add TBSCl (silyl ether) (t-butyl silyl chloride) to convert the OH into an ether and then use TBAF (tetrabutyl fluorine) to deprotect the OH