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Flashcards in Chemistry Reactions Deck (41):
1

Acyl chloride + Alcohol

RCOCl + HOR' ---> RCOOR' + HCl
Acylation, esterification
Room temperature

2

Ester ---> Alcohol and Carboxylic Acid

RCOOR' ---> RCOOH + HOR'
Heat under reflux with water and H+ ions (reversible reaction)
Hydrolysis reaction

3

Alcohol + Carboxylic Acid ---> Ester

RCOOH + R'OH ---> RCOOR' + H20
Esterification, condensation reaction
Heat under reflux with c.H2SO4 or HCl

4

Coupling Reaction
(Diazonium to Azo)

Benz-N2+ + Benz-X ---> Benz-N2-Benz-X (azo) + H+
Make solution of coupling agent
-in NaOH if phenol
- X must be OH or NH2. Increase electron density and reactivity to electrophiles
Add Ice cold diazonium salt solution
Electrophillic Substitution`

5

Alkane ---> Haloalkane

RCH3 + Br2 ---> RCH2Br + HBr
Radical chain reaction
Need Br2 and sunlight
(Normal initiation, propogation, termination reaction)

6

Diazotisation
(Aromatic amine to diazonium compound)

Benz-NH2 + HNO2 + H+ ---> Benz-N2+ + 2H20
Aromatic amine dissolved in dilute HCl. Cold sodium nitrate (III( solution added (NaNO2). HCl and NaNo2 form unstable nitrous acid which reacts with amine group
Need sodium nitrate(III) solution, dilute HCL, keep under 5 C

7

Haloalkane + OH- ---> Primary alcohol

RCH2Br + NaOH ---> RCH2OH + NaBr
Heat under reflux with NaOH (for hydroxide ions)
Nucleophillic substitution

8

Haloalkane + H2O ---> Primary alcohol

RX + H2O ---> ROH + H+ + X-
Heat under reflux with water. Slower than reaction with OH-
Nucleophillic substitution

9

Primary alcohol ---> Haloalkane

RCH2OH + X- + H+ ---> RCH2X + H20
Heat under reflux with NaBr (Br- ions) and c. Sulfuric acid
Nucleophillic substitution

10

Nitrobenzene ---> Phenylamine
Benz-NO2 ---> Benz--NH2

Data sheet
Reduction
Heat under reflux with SN and c.HCl

11

Benzene ---> Nitrobenzene
(nitration)

Benz + HNO3 ---> Benz-NO2 + H2O
Conc. HNO3 catalyst. Keep under 55
Electrophillic substitution
1) HNO3 + 2H2SO4 ---> NO2+ + 2HSO4- + H30+
- products are the nitrating mixture
2) Benz + NO2+ ---> Benz-NO2 + H+
3) H+ + 2H2SO4- + H3O+ ---> 2H2SO4 + H20

12

Benzene- Sulfobenzene
(sulfonation of benzene)

Benz + c.H2SO4 ---> Benz-SO3H + H+
Heat under reflux with c. H2SO4. OR at 40 with fuming H2SO4
Electrophillic substitution
1) H2SO4 ---> H2O + SO3+
2) Benz + SO3+ ---> Benz-HSO3+
Benz-HSO3 ---> Benz-SO3H

13

Benzene ---> Chlorobenzene
(chlorination)

Benzene + Cl2 ---> Benz-Cl + HCl
React at room temperature with anhydrous AlCl3
Electrophillic substitution
1. Cl2 + AlCl3 ---> Cl+ + AlCl4-
2. Benz + Cl+ ---> Benz-Cl + H+
3. H+ + AlCl4- ---> HCl + AlCl3

14

Benzene ---> Bromobenzene
(bromonation

Benzene + Br2 ---> Benz-Br + HBr
Heat with Iron(III) bromide catalyst
Electrophillic substitution
1. Br2 + FeBr3 ---> Br+ + FeBr4
2. Benzene + Br+ ---> Benz-Br + H+
3. H+ + FeBr3- ---> HBr + FeBr3

15

Benzene ---> Benzene-R
(Friedel-Crafts alkylation)

Benzene + RCl ---> Benz-R + HCl
Heat under reflux with R and anhydrous AlCl3
Electrophillic substitution
1. RCl + AlCl3 ---> R+ + AlCl4-
2. Benzene + R+ ---> Benzene-R + H+
3. H+ + AlCl4- ---> HCl + AlCl3

16

Benzene --->Benzene-OR
(Friedel-Crafts Acylation)

Benzene + RCOCl ---> Benz-OR + HCl
React with acyl chloride with anhydrous AlCl3 catalyst. Or use an acid anhydride
Electrophillic substitution
1. RCOCl + AlCl3 ---> RCO+ + AlCl4-
2. Benzene + RCO+ ---> Benz-C(O)R + H+
3. H+ + AlCl4- ---> HCl + AlCl3

17

Haloalkane ---> Amine

RX + NH3 ---> RNH3+X- RNH2 + X- + H+
Nucleophillic substitution
Heat in a sealed tube with c. NH3 solution

18

Electrophillic substitution

Bromination, Chlorination, Friedel-Crafts, Nitration, Sulfonation
Need some kind of catalyst to make the electrophile
Keeps stable benzene system

19

Nucleophillic addition

Aldehyde/ketone + cyanohydrin reactions
CN acts as nucleophile

20

Electrophillic addition

CH2CH2 + X-X ---> CH2XCH2X
Electrophile may be polarised by proximity to negative region
Electrons from negative region attack positive electrophile (whose electrons move to negative region)
Double bond breaks, making one carbon a carbocation and X ion
Electrons from X ion attacks carbocation to form covalent bond

21

Aldehyde/Ketone ---> Cyanohydrin
(R-C-OH)
(R'/ \CN)

RC(O)R' + CN- ---> R(R')C(OH)(CN)
React in solution, in acidic conditions with CN- ions
Nucleophillic addition

22

Nucleophile

Nucleophile- (molecule/ negative ion) with a lone pair of electrons that it can donate to a positively charged atom to form a covalent bond

23

Alkene ---> Haloalkane

CH2H2 + HBr ---> CH3CH2Br
React at room temperature with a solution of HBr
(Electrophillic addition)
OR a radical chain reaction with HBr(g)

24

Alkene ---> Alkane

CH2CH2 + H2 ---> CH3CH
150 c, 5atm, Finely powdered Nickel catalyst, H2 gas
Electrophillic addition

25

Alcohol ---> Carboxylic Acid

ROH ---> ROOH
Heat under reflux with excess chromate ions and H+
Oxidation

26

Aldehyde ---> Carboxylic Acid


Heat under reflux with acidified potassium dichromate
Oxidation

27

Aldehyde ---> Primary Alcohol

Reduction with NaBH4
Data sheet

28

Primary Alcohol ---> Aldehyde

ROH ---> RCHO
Heat under reflux with acidified potassium dichromate. Distil in situ. Excess alcohol
Oxidation

29

Secondary alcohol ---> Ketone

R(H)OHR' ---> RC(O)R'
Heat under reflux with acidified potassium dichromate
Oxidation

30

Primary alcohol ---> Alkene

ROH ---> R + H20
Dehydration. Elimination.
300 C with Alumina catalyst (Al2O3)
or Heat under reflux with c. H2SO4

31

Alkene ---> Primary alcohol

Alkene + H20 ---> Alcohol
Electrophillic Addition
Industrial- High temp, high pressure, presence of catalyst (phophoric acid on silica)
Lab- React ethene with c. H2SO4 then dilute with water. Adds on OSO3H group, the lose SO3H to OH- ions and gain H+

32

Carboxylic Acid ---> Acyl chloride

RCOOH +SOCl2 ---> RCOCl + SO2 + HCl
Substitution reaction
Heat under reflux with SCl2O

33

Acyl chloride ---> Secondary amide

RCOCl + RNH2 ---> RC(O)NHR + HCl
Acylation reaction, Condensation
Room temperature, RNH2

34

Haloalkane ---> Nitrile

R-X + CN- ---> RCN + Br-
Data sheet

35

Acyl Chloride ---> Primary amide

RCOCl + R'NH2 ---> RCONHR' + HCl
Acyl chloride + amine ---> amide + HCl

36

Nitrile ---> Carboxylic Acid

RCN ---> RCOOH
Heat under reflux, H+ ions
Data sheet

37

Nitrile ---> Amine

Nitrile + 2H2 ----> CHNH2
Palladium catalyst, high temp and pressure
(May not be necessary)

38

Nucleophillic substitution

Nucleophile attacks delta -ve C atom
Nucleophile donate two electrons to form dative covalent bond
C-X bond breaks heterolytically, producing negative ion
R-X + Nu- ---> R-Nu + X-

39

Electrophile`

A positive ion/ partial positive molecule, that will be attracted to a negatively charged region and react by accepting a lone pair of electrons to form a covalent bond

40

Amide ---> Carboxylic acid
(acid hydrolysis)

Amide + Acid ---> Carboxylic acid + Amine salt

41

Amide
(alkaline hydrolysis)

1 Amide + alkali ---> Carboxylate ion + ammonia (g)
2 Amide + alkali ---> Carboxylate ion + amine
Need mod concentrated alkali (NaOH)