Functional Group 3

Question 1

Williamson synthesis (synthesis of ethers)

Answer 1

1. )ROH -Na/K/NaH-> RO- M^+ + (1/2)H2

2. ) RO- + R’X -> R-O-R’ + X-

Question 2

Intermolecular dehydration (synthesis of ethers)

Answer 2

2ROH + H2SO4 -> ROR + H2O

R is primary

Question 3

Cleavage by HBr or HI (reactions of ethers)

Answer 3

1. ) ROR’ + HX -> ROHR’ -> RX + R’OB

2. ) R’OH + HX -> R’X + H2O

Question 4

Epoxides

Answer 4

Are cyclic ethers with three members rings

Question 5

Peroxyacid epoxidation

Answer 5

Alkene + R-CO-OOH -> epoxides + R-CO-OH

Question 6

Synthesis of epoxides from halohydrins

Answer 6

H2COH-CH2X + base -> H2COCHHX

Question 7

Acid catalyzed cleavage with H2O

Answer 7

Simple epoxide -acid,H2O-> OHCH2-CHOH anti-diol

Question 8

Acid-catalyzed cleavage with ROH

Answer 8

Simple epoxide -acid,ROH-> CH2OH-CH2OR

Question 9

Acid-catalyzed cleavage with hydrophilic acids

Answer 9

Simple epoxide -HX-> CH2OH-CH2X -HX-> CH2X-CH2X

Question 10

Base-catalyzed cleavage with alkoxides

Answer 10

Simple epoxide -(RO^-)-> CH2OH-CH2OR

Question 11

Base-catalyzed cleavage with organometallic compounds like GR

Answer 11

Simple epoxide -RM,H2O-> CH2OH-CH2R

Question 12

Sulfides

Answer 12

Thioesters- contain a sulfur atom between R groups

Question 13

Williamson displacement of RS (synthesis of sulfides)

Answer 13

1. ) RSH + NaOH -> RS-

2. ) RS- + R’X -> R-S-R’ + NaX

Question 14

Synthesis of sulfonium salts (reactions of sulfides)

Answer 14

R-S-R + R’Br-> R2R’S:^+ X^-

(CH3)2S: + CH3CH2Br -> [(CH3CH2OH)2SCH2CH3]^+Br^-

Question 15

Hydrogenylsis (reactions of sulfides)

Answer 15

R-S-R’ + H2 -Raney Ni catalyst-> RH + R’H + H2S

Question 16

Aromaticity implies 1

Answer 16

A cyclic structure with conjugated pi bonds containing unhybridized p orbitals that can overlap with other ring carbons to form a delocalized pi e- system

Question 17

Aromaticity implies 2nd

Answer 17

A structure in which delocalization of the pi-e- system lowers the total electronic energy

Question 18

Hückel’s rule

Answer 18

A compound is aromatic if the number of its pi electrons is equal to 2+4n, where n is zero or an internet snd represents filled electron shells; for n=0,1,2, aromatic systems have 2,6,10 pi electrons

Question 19

Antiaromatic

Answer 19

When pi electron delocalization increase the electronic energy

Question 20

Antiaromatic

Answer 20

A compound is antiaromatic if the number of its pi electrons is equal to 4n; for n=1,2,3, antiaromatic systems have 4,8,12 pi electrons

Question 21

Halogenation of benzene

Answer 21

Benzene + Br2 -FrBr3-> bromobenzene + HBr

Question 22

Nitration of benzene

Answer 22

Benzene + HNO3 -H2SO4-> nitrobenzene + H2O

Question 23

Sulfonation of benzene

Answer 23

Benzene + SO3 -H2SO4-> benezenesulfonic acid

Question 24

Alkylation (Friedel-Crafts) of benzene

Answer 24

Benzene + (CH3)3CCl -AlCl3-> t-butylbenzene + HCl

Question 25

Acylation (Friedel-Crafts) of benzene

Answer 25

Benzene + CH3CH2-CO-Cl

-AlCl3-> phenyl ethyl ketone + HCl

Question 26

Gatterman-Koch Synthesis

Answer 26

Benzene + CO/HCl -AlCl3,CuCl-> benzaldehyde

Question 27

Chlorination of benzene

Answer 27

Benzene + 3Cl2 -temp,pressure-> hexachlorocyclohexane

Question 28

Birch reduction of benzene

Answer 28

Ethylbenzene -Na/Li/NH3/ROH-> 1-ethyl-2,5-cyclohexadiene

Question 29

Catalyzed hydrogenation of benzene

Answer 29

o-diethylbenzene +3H2 -Ru,Rh/temp,pressure-> 1,2-diethylcyclohexane

Question 30

Clemmensen reaction of benzene

Answer 30

Acylbenzene -Zn/Hg,HCl-> alkylbenzene

Question 31

Oxidation by KMnO4 for benzene

Answer 31

Toluene -KMnO4,HCl-> benzoic acid salt

Question 32

Halogenation of side chain for benzene

Answer 32

Alkylbenzene -X2,light-> halogenated alkylbenzene

Question 33

Hydrogenolysis of alcohols (benzene)

Answer 33

Benzoyl alcohol -H2,Pd-> toluene

Question 34

Hydrogenolysis of ethers (benzene)

Answer 34

Benzyl cyclohexyl ether -H2,Pd-> cyclohexanol + toluene