Exam 5 Reactions

Question 1

Alcohol reaction: HBr

Answer 1

-Primary and secondary undergo SN2
-Tertirary undergo SN1
-Start with alcohol, substitute for halogen
-Rearrangement can occur (?)
-racemic micture with stereochem

Question 2

Alcohol reaction: PBr2

Answer 2

-Start with alcohol, substitute for halogen
-Rearrangement can occur (?)
-Stereochemistry inverts
-SN2 reaction

Question 3

Alcohol reaction: SOCl2

Answer 3

-Starts with alcohol, substitute for Cl
-SN2 reaction
-Rearrangement can occur (?)
-Stereochemistry inverts

Question 4

Alcohol reaction: TsCl

Answer 4

-Starts with alcohol, substitutes for Tosylate (OTs)
-Same stereochemistry

Question 5

Alcohol reactions: 1) NaBH4 2)MeOH

Answer 5

-Reduction reaction
-Reduces aldehydes and ketones only
-Converts carbonyl group into alcohol

Question 6

Alcohol reaction: 1) LiAlH4 2) H3O+

Answer 6

-Recuction reaction
-Reduces aldehydes, ketones, carboxylic acids, and esters
-Converts carbonyl group to alcohol

Question 7

Alcohol reaction: PCC

Answer 7

-Oxidation reaction
-Converts alcohol to carbonyl group
-Weaker of the two
-Stops at aldehyde for primary alcohols
-Ketones for secondary alcohols

Question 8

Alcohol reaction: 1) Na2Cr2O7 2) H3O+

Answer 8

-Oxidation reaction
-Converts alcohol into carbonyl group
-Stronger of the two
-Stops at carboxylic acids for primary alcohols
-Ketones for secondary alcohols

Question 9

Alcohol reaction: Grignard reagents

Answer 9

-Formula: R-MgX
-Adds additional carbons to a carbonyl group, converting it to an alcohol
-Reacts twice with esters, resulting in two R groups

Question 10

Alcohol reaction: 1) BH3, THF 2) H2O2, NaOH

Answer 10

-Hydroboration Oxidation
-Converts alkene to alcohol by adding H-OH across the double bond
-Anti Markovnikov addition (least substituted cabon)

Question 11

Alcohol reaction: 1) Hg(AOc)2 2) NaBH4

Answer 11

-Oxymercuration Demurcuration
-Converts alkene to alcohol by adding H-OH across the double bond
-Markovnikov addition (More substituted carbon)

Question 12

Alkyne reaction: 1) H2 2) Pd/C

Answer 12

-Syn addition of hydrogen
-Converts alkyne all the way to alkane

Question 13

Alkyne reaction: 1) H2 2) Lindlar’s catalyst

Answer 13

-Syn addition of hydrogen
-Cis alkene
-Stops at the alkene stage

Question 14

Alkyne reaction: 1) Na 2) NH3(l)

Answer 14

-Anti addition of hydrogen
-Trans alkene

Question 15

Alkyne reaction: 1) HgSO4 2) H2O, H2SO4

Answer 15

-Results in a ketone
-Adds to more substituted carbon
-Enol tautomerizes to a ketone
-If asymmetrical, we get a mixture of products where the ketone is added to either side of the double bond

Question 16

Alkyne reaction: 1) R2BH 2)H2O2, NaOH

Answer 16

-Results in an enol that tautomerizes to an aldehyde
-Terminal alkynes
-Adds to least substituted carbon

Question 17

Alkyne reaction: HBr

Answer 17

-Results in an alkene
-Adds bromine to secondary carbon
-If we use excess bromine, it reduces further to an alkane with two bromines on the same carbon
-Racemic when the structure is asymmetrical

Question 18

Alkyne reaction: 1) HBr 2) ROOR

Answer 18

-Bromine is added to primary carbon instead of secondary
-Terminal alkynes
-Mixture of isomers (E and Z)

Question 19

Alkyne reaction: Br2

Answer 19

-Bromine added in anti addition to both sides of double bond
-Converts alkyne to alkene
-If we use excess bromine, converts to an alkane with one more bromine atoms on each carbon (2 total per carbon)

Question 20

Alkyne reaction: 1)NaNH2 2) R-Br

Answer 20

-Adds extra carbons to an alkyne
-Triple bond remains

Question 21

Alkyne reaction: 1) O3 2) H2O

Answer 21

-Oxidative cleavage across the triple bond
-Results in two different structures
-Terminal alkynes: Carboxylic acid and carbon dioxide
-Internal alkynes: Two carboxylic acids