Advanced Higher Unit 3- Organic Chemistry

Advanced Higher Chemistry

Unit 3 - Organic Chemistry

PERMEATING ASPECTS & REACTION MECHANISMS

Learning Outcomes Questions & Answers

KHS Chemistry Jan 2007 page 1 Permeating Aspects & Reaction Mechanisms Advanced Higher Unit 3- Organic Chemistry 1. PERMEATING ASPECTS (Of Organic Chemistry)

Reaction Types 3.1.1 Equations can be written for the following reaction types and, given equations, these reaction types can be identified. substitution addition elimination condensation hydrolysis oxidation reduction

Reaction Mechanisms 3.1.2 The following reaction mechanisms can be described in terms of electron shifts. ( i) substitution of

( ii) electrophilic addition to

carbocation mechanism cyclic intermediate mechanism (iii) nucleophilic substitution

SN1 and SN2

Hydrocarbons & 3.2.4 Alkanes undergo substitution reactions with and by a chain reaction mechanism.

3.2.5 The chain reaction includes the following steps ( i) initiation by homolytic fission to produce radicals ( ii) propagation (iii) termination

3.2.7 Alkenes can be prepared in the laboratory by ( i) dehydration of using aluminium oxide, concentrated sulphuric or orthophosphoric acid (ii) base-induced elimination of hydrogen halides from monohalogenoalkanes.

3.2.8 Alkenes undergo: ( i) catalytic addition with hydrogen to form alkanes ( ii) addition with halogens to form dihalogenoalkanes (iii) addition with hydrogen halides according to Markownikoff’s rule to form monohalogenoalkanes ( iv) acid-catalysed addition with water according to Markownikoff’s rule to form alcohols.

3.2.9 The mechanisms of the above reactions involve ( i) for halogenation cyclic ion intermedate ( ii) for hydrohalogenation carbocation intermediate (iii) for acid catalysed hydration carbocation intermediate

KHS Chemistry Jan 2007 page 2 Permeating Aspects & Reaction Mechanisms Advanced Higher Unit 3- Organic Chemistry 3.2.12 Monohalogenoalkanes undergo nucleophilic substitution reactions.

3.2.13 Monohalogenoalkanes undergo elimination reactions to form alkenes.

3.2.14 Monohalogenoalkanes react with: ( i) alkalis to form alcohols ( ii) alcoholic alkoxides to form ethers (iii) ethanolic cyanide to form nitriles which can be hydrolysed to carboxylic (chain length increased by one carbon atom) ( iv) ammonia to form amines via alkyl ammonium salts.

Alcohols and ethers 3.2.17 Alcohols can be prepared from ( i) alkenes by hydration (ii) halogenoalkanes by substitution.

3.2.19 Alcohols react with some reactive metals to form alkoxides .

3.2.20 Alcohols can be dehydrated to alkenes.

3.2.21 Alcohols undergo condensation reactions slowly with carboxylic acids and more vigorously with acid chlorides to form esters.

3.2.27 Ethers can be prepared by the reaction of halogenoalkanes with alkoxides.

Aldehydes, ketones & carboxylic acids 3.2.31 and ketones can be reduced to primary and secondary alcohols, respectively, by reaction with lithium aluminium hydride in ether.

3.2.32 Aldehydes and ketones undergo ( i) addition reactions in which the carbon atom in the polar carbonyl group submits to nucleophilic attack.

(ii) condensation reactions with derivatives of ammonia (XNH2)

which proceed by nucleophilic addition of XNH2 followed by elimination of a water molecule.

3.2.39 Carboxylic acids can be prepared by: ( i) oxidising primary alcohols and aldehydes ( ii) hydrolysing nitriles, esters or amides

3.2.40 Reactions of carboxylic acids include: ( i) formation of salts by reactions with metals, carbonates and alkalis ( ii) condensation reactions with alcohols to form esters (iii) reaction with ammonia or amines and subsequent heating of the ammonium salt to form amides

( iv) reduction with LiAlH4 to form primary alcohols. KHS Chemistry Jan 2007 page 3 Permeating Aspects & Reaction Mechanisms Advanced Higher Unit 3- Organic Chemistry Aromatics 3.2.49 Most reactions of involve attack of an on the cloud of delocalised electrons, that is electrophilic substitution.

3.2.50 Benzene resists addition reactions but undergoes electrophilic substitution reactions. These include: ( i) chlorination and bromination to produce chlorobenzene and bromobenzene ( ii) nitration to produce nitrobenzene (iii) sulphonation to produce benzene sulphonic acid ( iv) to produce alkylbenzenes.

KHS Chemistry Jan 2007 page 4 Permeating Aspects & Reaction Mechanisms Advanced Higher Unit 3- Organic Chemistry El e c t r o p h i l i c Ad d i t i o n El e c t r o p h i l i c Ad d i t i o n (c a r b o c a t i o n i n t e r m e d i a t e ) (c a r b o c a t i o n i n t e r m e d i a t e )

H H H H | | | | H — C = C — H H — C = C — H Though water is polar, the presence of H+ H makes this reaction easier δ+ As the polar HBr + (catalyst). H molecule approaches, π H O π electrons from the C=C electrons from the C=C | bond come out to form a bond come out to form H a new bond with the H+ δ— new bond with the Br Hydrogen atom. ion

The electrons of the H—Br bond H H move onto the bromine to form a bromide ion, Br—. | | H — C — C — H H H ⊕ | H | | H :O H — C — C — H ⊕ H | The carbocation is now attacked by

H — a lone pair on the oxygen atom :Br The carbocation is then attacked by H H the lone pair of the bromide ion, a neucleophile. | | H — C — C — H H H | | ⊕ | | H O — H H — C — C — H | | | H H Br A hydrogen ion is reformed (catalyst) and an alkanol is pro- A monohaloalkane is prduced and overall the reaction can be duced. Overall the reaction can be represented by the equa- represented by the equation: tion:

C2H4 + HBr → C2H5Br C2H4 + H2O → C2H5OH

Ad d i t i o n Ad d i t i o n , Hy d r a t i o n KHS Chemistry Jan 2007 page 5 Permeating Aspects & Reaction Mechanisms Advanced Higher Unit 3- Organic Chemistry El e c t r o p h i l i c Ad d i t i o n Fr ee Ra d i c a l (c y c l i c i o n i n t e r m e d i a t e ) Su b s t i t u t i o n

In i t i at i o n H H UV radiation is | | absorbed ‘half arrows’ are used to show the movements of H — C = C — H single electrons Cl : Cl

As the non-polar Br2 δ+ molecule approaches, π Br electrons from the C=C Homolytic fission results in the bond induce polarity and formation of two chlorine free 2 Cl• | then come out to form a radicals δ— new bond with the nearer Br Bromineatom. Pr o p a g a t i o n The electrons of the Br—Br bond move onto the further bromine to form a bromide ion, Br—. • • Cl H — CH3 → HCl + CH3 :Br — H • → • H — C — C — H CH3 Cl— Cl HCl + Cl ⊕ H A series of reactions between a free radical and a molecule Br keep the reaction going. Instead of a carbocation being formed, the positive charge is shared between the 2 carbon atoms and the Because each step makes another free readical, the reaction bromine atom. The Bromide ion (nucleophile) will then is a chain reaction. attack from the other side. A TRANS arrangement. Te r m i n a t i o n Br H | | Cl• •CH → CH Cl H — C — C — H 3 3 | | Any collisions betwee two free radicals will stop a chain. H Br

A dihaloalkane is prduced and overall the reaction can be A mixture of haloalkanes will be produced but the first represented by the equation: stage can be represented by the equation:

C2H4 + Br2 → C2H4Br2 CH4 + Cl2 → CH3Cl + HCl

Ad d i t i o n Su b s t i t u t i o n KHS Chemistry Jan 2007 page 6 Permeating Aspects & Reaction Mechanisms Advanced Higher Unit 3- Organic Chemistry Nu c l e o p h i l i c s u b s t i t u t i o n Nu c l e o p h i l i c s u b s t i t u t i o n (Sn1) (Sn2)

R' R' — R — C δ+ — Br δ— Nu C δ+ — Br δ— The nucleophile R'' The polar C—Hal bond breaks approaches the R R'' heterolytically. electon deficient carbon

A carbocation is At this stage the molecule is The intermediate is a produced which can R' trigonal planar and trigonal bipyramid R' be attacked by any nucleophilic attack from shape nucleophilic group ⊕| either side is equally likely. | C Nu C Br R R'' R R'' — Nu Nu : As the nucleophiles' electron pair moves in, the electons of the C—Br bond move onto the bromine

If R , R' and R'' are all different (assymetric carbon), then Even if R , R' and R'' are all different (assymetric carbon), a mixture of optical isomers will be produced. only one possible isomer can be produced.

Nucleophiles include: Nucleophiles include: : : — — → → : HO: alcohols HO alcohols (NaOH(aq) or other aqueous solutions) (NaOH(aq) or other aqueous solutions) : : — — → → : RO: ethers RO ethers (Alkoxide ions, from Na/alcohols) (Alkoxide ions, from Na/alcohols)

H3N: → amines H3N: → amines (Ammonia) (Ammonia)

— — CN: → nitriles CN: → nitriles (Alcoholic cyanides) (Alcoholic cyanides)

A variety of products can be made by this reaction but overall A variety of products can be made by this reaction but over- the reaction can be represented by the equation: all the reaction can be represented by the equation: R—Hal + Nu → R—Nu + Hal— R—Ha + Nu → R—Nu + Hal—

Su b s t i t u t i o n Su b s t i t u t i o n The first step is therate determining step and, since it only The rate determining step involves both chemicalss so the involves one substance, the reaction is first order reaction is second order

Sn1 or Sn2 ? Can depend on the polarity of the C—Hal bond. Can depend on the polarity of the solvent used. Can depend on the size of the R , R' and R'' groups. No easy answer. Just need to be aware of the the two possibilities. KHS Chemistry Jan 2007 page 7 Permeating Aspects & Reaction Mechanisms Advanced Higher Unit 3- Organic Chemistry Al c o h o l El i m i n at i o n Ha l o a l k a n e El i m i n at i o n (u s i n g a c i d ) (e t h a n o l i c KOH) H H H H

: | | | |

HO: — C — C — H H — C — C — Br | | H | H + H H H — A lone pair from the hydroxyyl oxygen forms a new bond HO: : + with the H ion. The ibecomes protonated. The OH— ion acts like a base by removing a Hydrogen from the molecule as an H+ ion.

H H The electrons move from the C—H bond to form a π bond between the 2 carbon atoms. ⊕ | | The electrons move from the C—Br bond to HO — C — C — H form a bromide ion which is eliminated. | | | H H H H H The electrons of the C—O bond move onto the | | oxygen and a water molecule is eliminated H — C = C — H

H H A carbocation is formed. A hydrogen atom and a bromine atom have been eliminated from the molecule to form an . Overall the reaction can | | be represented by the equation: ⊕ C — C — H C2H5Br → C2H4 + HBr Electrons move from the | | C—H bond to form a π bond El i m i n at i o n H H between the 2 carbon atoms

A hydrogen ion is eliminated , replacing H H + the original H ion. | | H — C = C — H

An alkene is prduced and overall the reaction can be represented by the equation:

C2H5OH → C2H4 + H2O

El i m i n at i o n (De h y d r a t i o n ) KHS Chemistry Jan 2007 page 8 Permeating Aspects & Reaction Mechanisms Advanced Higher Unit 3- Organic Chemistry El e c t r o p h i l i c Su b s t i t u t i o n This is the main reaction of benzene rings. Though they have even more π electrons than the C = C bond in alkenes, they resist addition because the loss of the delocalised ring is too destabilising.

Al k y l a t i o n - u s i n g a l k y l h a l i d es /AlCl3 Ha l o g e n a t i o n - u s i n g Ha l o g e n s /AlCl3 The production of the electrophile requires the presence of The production of the electrophile is helped by the presence th AlCl3 . (The Al make use of its empty 4 orbital). of AlCl3 . The reaction would be very slow otherwise.

— — An AlCl4 ion is An AlCl4 ion is H also formed also formed

H — C — Cl : AlCl3 Cl — Cl : AlCl3 H

⊕ ⊕ CH3 Cl π electrons move from the π electrons move from the ring to form a new bond with ring to form a new bond with the chlorine ion, Cl+. the methyl ion.

H CH3 H Cl The positive charge is shared The positive charge is shared over the whole ring. ⊕ over the whole ring. ⊕ Electrons move from the C—H Electrons move from the C—H bond, a H+ ion is eliminated. bond, a H+ ion is eliminated.

CH3 Cl Overall, an alkyl group takes the place Overall, a halogen atom takes the place of a hydrogen atom, Su b s t i t u t i o n . of a hydrogen atom, Su b s t i t u t i o n .

+ — + — The H ion reacts with the AlCl4 to reform The H ion reacts with the AlCl4 to reform

AlCl3 and a molecule of HCl. AlCl3 and a molecule of HCl.

Ni t r a t i o n - u s i n g H2SO4/HNO3 Su l p h o n a t i o n - u s i n g H2SO4/SO3 + The production of the electrophile , NO2 is a result of a The electrophile is a molecule of SO3. The 3 oxygen atoms reaction between these two strong acids. are more electronegative; a large δ+ forms on the sulphur.

→ — + + δ− 2 H2SO4 + HNO3 2 HSO4 + NO2 + H3O O δ+S Oδ− π electrons move from the ring to form a new bond with ⊕ δ− π electrons move from the O NO2 the sulphur trioxide, SO3. ring to form a new bond with Electrons also move in one of the S—O the nitro ion, NO +. 2 bonds. O−

H NO2 H S O The positive charge is shared The positive charge is shared O over the whole ring. ⊕ over the whole ring. ⊕ Electrons move from the C—H Electrons move from the C—H + bond, a H+ ion is eliminated. bond, a H ion is eliminated. OH

+ NO2 S O The H ion that is eliminated from Overall, a nitro group takes the place of Othe benzene ring attaches itself to the a hydrogen atom, Su b s t i t u t i o n . oxygen ion.

Overall, a HSO3 group takes the place of a hydrogen atom, Su b s t i t u t i o n .

KHS Chemistry Jan 2007 page 9 Permeating Aspects & Reaction Mechanisms +

Advanced Higher 5 Unit 3- Organic Chemistry H 2 Na s

+ - — s H O (H /OH ) s r 2 NaOH

e

→ → l t

4 2 SO t c.H / alcohol COOH c i d

← ← a COO 3 s COOC 3 S 3 A HCl E CH CH CH

es 4

2001

SO 4 t i v 2 a h SO 2 r i v 4 r c e a t i o n s

COOH D

alcohol / c.H / alcohol a / dil H 2 → 7 o p h i l i c LiAlH O c i d e 2 d u c t i o n CH x i d 3 A e d d i t i o n Cr es 2 K O R A CH u c l

- e.g 2,4-dinitrophenylhydrazine → ← N KH S M OH + COOCl 3 c h l o r i d

3 es →→ CH es c i d CHO h y d A 3 t o n e COCH 3 e CH l d K CH hydrolysis, dil Na A t i o n a → s x i d CN OH es 2 2 O 4 4 CH CH o 3 3 i t r i l

SO SO l c o h o l - N 2 2 N CH CH A 4 4 t i o n t i o n a a / dil H / dil H 4 7 7 LiAlH LiAlH d u c t i o n

d u c t i o n

O O alcoholic CN alcoholic 2 2 x i d x i d e e Cr Cr 2 2 O R - O LiAlH R K K 2 ← → ← → ← → NH 2 es alkali, OH s CH 3 s s

3

m i n 3 3 o p h i l i c

CH

e A → t i t u t i o n

conc. NH conc. s 3 → es l c o h o l OH

u c l n

2 u b l c o h o l l c o h o l CH → a A )(OH)CH S N 2 3 A CH A 3 Cl l k r y CH(OH)CH s 2 3 r y a a r y r t i o n

OCH alcoholic a CH e a a 2 CH C(CH CH ← n o 3 - 3 e t h Alkoxide, OR r t i CH r i m c o n d 3 E e CH CH P e 4 T l o g S l i m i n CH a PO 3 E H or H 4 4 t i o n SO SO 2 t i o n a 2 a es )

e n O / c.H y d r 2 t R h y d r e a H e e H

t i o n

n n z d i HCl a

d d i t i o n e D es e e alcoholic KOH alcoholic (400°C) or c.H 3 n 2 ← → n z O a A r m 2 e e r b o c NO Al

l k

a ← → c i d l k y l b a c i n t a Cl

2 A 2 es i t r o b n o ) n e e

N

(

t e 2 2 or Br or Cl =CH

← O a 2 ClCH l k i o n l o g 2 d i

e a c t r o p h i l i c CH A S e CH OH O i h u l p h o n i c

r m + l e m i s t r y

e 2 D S E

h nitration NO e c y c l i c / R—Hal ( i n t 3 n e alkylation C AlCl n z e e r B / heat c k i n g h / Ni 3 → 2 O a 2

H sulphonation

d d i t i o n 3 i g r es / SO Al →SO 4 A n 2 C c.H t i t u t i o n a H s l e

→c t r o p h i l i c l k n a e → ← a u b Cl e l Cl S 2 E n z n o d i c e n c e d t i t u t i o n 3 es e e n a s a n CH

reforming e halogenation

3

CH a

R 2 2 or Br or ←Cl 3 → → l o b u b l o g n z d v RE A CTI O N PA T HWA YS

CH Cl / Br

l k 2 2 a a e S CH A A H B KHS Chemistry Jan 2007H page 10 Permeating Aspects & Reaction Mechanisms Advanced Higher Unit 3- Organic Chemistry s e s HSN14290 d n i i H H e m t a links links o CN CN O O y r l P o HH HH many amide many P many peptide peptide many Unit 2 Flow Diagram Flow 2 Unit condensation polymerisation H

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KHS Chemistry Jan 2007 page 11 Permeating Aspects & Reaction Mechanisms Advanced Higher Unit 3- Organic Chemistry Q1 H | Br MgBr R—C—OH | | | Mg ( i) RCHO ethoxyethane (ii) hydrolysis

R = alkyl group or hydrogen

Using bromobenzene above and treating with propanone at (i), subsequent hydrolysis would result in the formation of

A B H CH3 | | CH3—C—OH CH3CH2—C—OH | |

C D OH H | | CH3—C—CH3 CH3—C—OCH3 | |

Q2 Which of the following does not involve a nucleophilic substitution of the organic compound?

- - A CH3CH2Br + OH → CH3CH2OH + Br

B —Cl

+ Cl2 → + HCl

- - C C2H5CH2Br + CN → C2H5CH2CN + Br

D CH3CH2Br + NH3 → CH3CH2NH2 + HBr

KHS Chemistry Jan 2007 page 12 Permeating Aspects & Reaction Mechanisms Advanced Higher Unit 3- Organic Chemistry Q3 Which of the following can behave as an electrophile?

A C2H5NH2 B HS-

C NH3 + D NO2

Q4 In each of the following compounds, the bonding shown is between carbon and one other element. In which compound is the bond polarised such that the carbon has a partial negative charge?

A H3C—Br

CH3CH

B O

C H3Si—CH3 CH C N D 3

- - Q5 OH + CO2 → HCO3

+ - C2H4 + Br2 → C2H4Br + Br

In the above two reactions, which two substances are acting as ? - A OH and Br2

- B OH and C2H4

C CO2 and Br2

D CO2 and C2H4

- + + - Q6 C2H5Br + C2H5O Na → C2H5OC2H5 + Na Br

This reaction is an example of A a condensation reaction to form an ether

B a condensation reaction to form an ester

C a nucleophilic substitution to form an ether

D an electrophilic substitution to form an ether

KHS Chemistry Jan 2007 page 13 Permeating Aspects & Reaction Mechanisms Advanced Higher Unit 3- Organic Chemistry Q7 The reaction scheme shown below is an example of a chain reaction.

⓵ Br2 → 2Br* initiation step

⓶ C2H6 + T → C2H5* + U

⓷ V + Br2 → C2H5Br + W ⓸ Br* + Br* → X

⓹ C2H5* + C2H5* → Y

⓺ C2H5* + Z → C2H5Br

a) Write down the species represented by the letters T to Z in the reaction scheme. 3

b) In step ⓵, the initiation step, explain if the process is exothermic or endothermic. 1

c) i) What name is given to the process represented by steps ⓶ and ⓷? 1 ii) What name is given to the process represented by steps ⓸ to ⓺? 1

d) Why is the reaction shown referred to as a chain reaction? 1 (7)

Q8 Haloalkanes are extremely versatile organic compounds and are widely used in syntheses and preparations, as indicated in the following flow diagram.

hydrolysis

→

CN— → OR— → → nitrile → ether ⓵ ⓸

OH— ⓷ NH3 ⓶ oxidation amine alcohol → carboxylic acid

R = alkyl group

a) Name the type of reaction involved in reactions ⓵ to ⓸. 1

b) Why can haloalkanes take part in the type of reaction in a)? 1

c) How is the reagent OR– obtained from an alcohol? 1

d) 1-bromopropane was used as the starting material for the preparation of carboxylic acids. Name the carboxylic acid formed: i) via route ⓷ ii) via route ⓵. 2

(5)

KHS Chemistry Jan 2007 page 14 Permeating Aspects & Reaction Mechanisms Advanced Higher Unit 3- Organic Chemistry Q9 Haloalkanes are suitable compounds from which to synthesise other compounds. The flow diagram below shows how different compounds can be prepared from 2-bromopropane.

reagent X 2-bromopropane → C3H7CN → →

+ reagent Y H (aq)

→ → compound P → C3H7COOH

C3H7OH → concentrated concentrated

H2SO4 H2SO4 140°C 60°C compound Q compound R

a) Draw the structural formula for 2-bromopropane. 1

b) Which single term is used to describe reagents X and Y? 1

c) The equation for the reaction that produces compound Q is:

H H | | H — C — H H — C — H | | → 2 C3H7OH H — C —— O —— C — H + H2O | | H — C — H H — C — H | | H H

Q is an ether. What name could be given to the reaction that produces this ether? 1

d) Draw the structural formula for an isomer of Q that belongs to a different homologous series. 1

e) Draw the structural formula for compound R. 1

f) Describe briefly how to distinguish between compounds Q and R. 1

g) Name the organic compound produced on oxidising compound P with acidified potassium dichromate solution. 1 (7)

KHS Chemistry Jan 2007 page 15 Permeating Aspects & Reaction Mechanisms Advanced Higher Unit 3- Organic Chemistry Q10 Consider the reaction sequence outlined below.

A → — C2H5OH C2H5O ⓵

→ an ether ⓶ B →  a secondary alcohol C3H7Cl

a) Give the name of ion ⓵. 1

b) Name: i) reagent A ii) reagent B. 2

c) Draw the full structural formula for compound ⓶. 1 (4)

Q11 Study the organic reactions below.

C2H5OH CH2 = CH2

⓵ ⓶

→ → C H Br 2 → 5

⓷

C H CN 2 → 5

⓸ → C2H5COOH→ →

⓹ ⓺ ⓻

C2H5COOCH3 C2H5COONH4 C2H5CHO

The reagents necessary to bring about the conversions are numbered. Copy the numbers and alongside each number put:

a) the type of reaction occurring 7

b) the appropriate reagent to bring about the conversion. 7 (14)

KHS Chemistry Jan 2007 page 16 Permeating Aspects & Reaction Mechanisms Advanced Higher Unit 3- Organic Chemistry Answers

Q1 C Q2 B Q3 D Q4 C Q5 C Q6 C

Q7 a) T – Br*; U – HBr; V – C2H5*; W – Br*;

X – Br2; Y – C4H10; Z – Br* (any 6 × ½) 3

b) Endothermic (1) Energy required to break bonds (1) 2

c) i) Propagation (1) ii) Termination (1) 2

d) Once the Br* radical is produced, the propagation step produces more of these radicals to keep the reaction going. 1 (8)

Q8 a) Nuclophilic substitution 1

b) They have a polar C–X bond. (X = halogen) 1

c) React the alcohol with an alkali metal (Na). 1

d) i) Propanoic acid (1) ii) Butanoic acid (1) 2 (5)

Q9 a) CH3CHBrCH3 as a full structural formula 1

b) Nucleophile 1

c) Condensation (Joining together with formation of water) 1

d) Ethers and alcohols are isomers , so any hexanol isomer,

e.g. CH3CH2CH2CH2CH2CH2OH 1

e)

1

f) (Use infra-red to detect the presence of C=O in R or its absence in Q); later in course ether has lower boiling point than ester; ester can be hydrolysed with NaOH but ether cannot be. (any one) 1

g) Propanone 1 (7) KHS Chemistry Jan 2007 page 17 Permeating Aspects & Reaction Mechanisms Advanced Higher Unit 3- Organic Chemistry Q10 a) Ethoxide ion 1

b) i) Sodium/alkali metal (1)

ii) PCl5/PCl3/AlCl3 (1) 2

c)

1 (4)

Q11 (i) (ii)

⓵ Substitution HBr/PBr3/PBr5 ⓶ Elimination Alcoholic KOH ⓷ Substitution KCN/NaCN/CN–

+ ⓸ Hydrolysis H (aq) ⓹ Condensation/

esterification CH3OH (concentrated H2SO4)

⓺ Neutralisation NH3

⓻ Chlorination PCl5/PCl3 /SOCl2

(7 × 1) (7 × 1) (14)

KHS Chemistry Jan 2007 page 18 Permeating Aspects & Reaction Mechanisms