FUNCTIONAL GROUPS 1

Question 1

How are Alkyl halides producecd using halogenation

Answer 1

Addition reaction- The double bond is attracted to the halogen which is delta positive and this causes the bond between the two halogens to break.

The halogen is initially bonded to both the carbons from the double bond however one takes the halogen and the other is left as a +ve carbocation.

The Carbocation then is bound to another halogen

When the second halogen is bound it binds in TRANS addition.

Question 2

Halogenation V hydrohalogenation

Answer 2

Halogenation = X₂

Hydrohalogenation = HX

Question 3

How are alky halides produced using hydrohalogenation?

Answer 3

Addition: HX The electrins from the Pi bond are attracted to the H this causes the HX bond to break.

One the H bonds with one of the carbons from the Pi bonds a carbocation forms and this attracts the negative halogen.

This follows Markovnikovs rule.

Question 4

What is the difference between 1^o, 2^o and 3^o carbocations

Answer 4

Primary is least stable tertiary is most stable

Question 5

What is the difference between Sn1 and Sn2 reactions?

Answer 5

Sn1 have a carbocation intermediate and require a leaving group. It is only dependant on the concentration of one molecule

Sn2 backside attack. Change configuration depend on the conc of 2 molecules. (R–> S, S–> R)

Question 6

What is the process of dehydration to form an alkene?

(what is the starting molecule, reagent and products)

Answer 6

Alcohol + conc. H₂SO₄

The product is alkene + water

* Saytizfs rule

Question 7

What is the process of dehalogenation to form an alkene?

Answer 7

Alky haide + KOH or NaOH in ethanol

An alkene and HX are produced.

Question 8

What is Hydrogenation of alkenes?

Answer 8

Alkene reacted with H2/Pt —> alkane

Add in Cis, the Pt “holds” the alkene so the New H+s add on the same side

Question 9

What is the process of hydrohalogenation?

Answer 9

Alkene + acid – diethyl ether—> Carbocation intermediate –> alkyl halide

Question 10

What is etherification?

Answer 10

Alkene + Alcohol _\_H+__> Ether

Question 11

What is Hydration of an alkene?

Answer 11

Alkene + H₂O –H+–> Alcohol

Question 12

What is the process of producing an alkyne

• Name of process
• reagents

Answer 12

1. Didehydrogenation of dihaloakanes
2. KOH or NaOH in ethanol

(NaNH₂ or NH₃ can work as well)

Question 13

What are the 3 reagents for Alkyne hydrogenation? what do each of them produce?

Answer 13

1. H2/Pt –> alkane
2. 1. Li/ liq NH₂ 2. H₂O –> E- alkene
3. Lindlar’s Catalyst –> Z-alkene

Question 14

What happens if H₂SO₄ is added to an Alkyne?

Answer 14

1. Secondary alcohol –> 2. Ketone/ Aldehyde (ethyne)

Question 15

What is the product of: Alkyne + HZ?

Answer 15

1. Alkenes (50-50 split for H/ Z placement/ Racemic)
2. Major/ minor alkenes if terminal alkyne

Question 16

How are alkynide ions created, and how are they helpful?

Answer 16

Terminal alkyne —NaNH₂—> RC_=_C-

Extend the carbon chain

Question 17

What is the structure of Aminobenzene amd what is the reagent required to make it?

Answer 17

A benzene ring with NH2 on one side. The step before is a conversion from NO2 –> NH2

There are 3 potential reagents; 1. Fe, Zn or Sn with H+ and 2.OH-

Question 18

What are the 4 strongly activating ortho/ para directors?

Answer 18

1. OH
2. NR₂
3. OR
4. NH₂

Question 19

What is the weakly activating O/P directors?

Answer 19

CH₃

Question 20

What are the deactivating O/P directors?

Answer 20

Halogens

Question 21

What are the strongly and moderately deactivating meta directors?

Answer 21

Strong- NO

Moderate- COH, COOH or C_=_N