all organic synthesis pathways Flashcards

1
Q

describe the 3 steps of free-radical substitution with halogens.

A

1) initiation
- produces free radical from molecules

2) propagation
- forms products & more radicals

3) termination
- removes free radicals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

under what conditions does alkanes react with halogens?

A

under UV light / on heat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what reaction conditions are involved in the electrophilic addition of H2 to alkenes? what is the product?

A

Ni catalyst, 150C, 5 atm
forms alkanes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what reaction conditions are involved in the electrophilic addition of steam to alkenes? what is the product?

A

conc. H3PO4 catalyst, 300-600C, 70 atm
produce alcohols

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what reaction conditions are involved in the oxidation of alkenes? what is the product?

A

acidified KMnO4 + steam
produce diols

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are the reagents, conditions & mechanism of bromination of benzenes?

A

mechanism: electrophilic substitution
reagent: Br2
conditions: room temp. & FeBr3 catalyst

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

draw the mechanism of electrophilic substitution of benzenes with bromine. *

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

draw the mechanism of nitration of benzenes. *

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what are the reagents, conditions & mechanism of chlorination of benzenes?

A

mechanism: electrophilic substitution
reagent: Cl2
conditions: room temp. & FeCl3 / AlCl3 catalyst

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what are the reagents, conditions & mechanism of nitration of benzenes?

A

mechanism: electrophilic substitution
reagents: conc. HNO3 & conc. H2SO4 catalyst
conditions: below 55C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the mechanism of friedel-crafts reactions?

A

electrophilic substitution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what are the reagents and conditions of friedel-crafts alkylation?

A

reagent - RCl (chloroalkyl compound)
conditions - anhydrous AlCl3 catalyst
- heat under reflux

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

draw the mechanism of friedel-crafts alkylation. *

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what are the reagents & conditions of friedel-crafts acetylation?

A

reagents - acyl chloride
conditions - anhydrous AlCl3 catalyst
- heat under reflux at 50C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

draw the mechanism of friedel-craft acetylation. *

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

describe the reagents and conditions of bromination of phenols.

A

reagents - bromine water
conditions - room temp.

17
Q

draw the mechanism of bromination of phenols. *

A
18
Q

why does phenols not require a halogen carrier?

A

lone pair on O on -OH group is partially delocalised in the ring & activates the ring
-> higher e- density & Br2 is more polarised

19
Q

how could 2,4,6-tribromophenol be identified?

A

white solid, antiseptic smell

20
Q

how could primary amines be formed from halogenoalkanes?

A

one-step nucleophilic substitution

21
Q

how could primary amines be prepared from nitriles?

A

1- convert halogenoalkane to nitrile
reagent- ethanol & KCN
conditions - heat under reflux

2- reduce nitrile to amine
reagent- LiAlH4 in dry ether

22
Q

how are aromatic amines formed from nitroarenes?

A

reagent- Sn & HCl
conditions - heat
mechanism - reduction

23
Q

what does grignard reagents do?

A

increase carbon chain length

24
Q

how are grignard reagents made?

A

halogenoalkane dissolved in dry ether & reacted with Mg

25
Q

what does grignard reagent & methanal form?

A

primary alcohol

26
Q

what does grignard reagent & aldehyde form?

A

secondary alcohol

27
Q

what does grignard reagent & carbon dioxide form?

A

carboxylic acid

28
Q

what are the conditions and reagents of oxidation of aldehydes? what is the product?

A

carboxylic acid
- heat under reflux
- K2Cr2O7 & dilute H2SO4

29
Q

what compound could be tested with fehling’s solution? state the conditions, reagents & observation.

A

aldehydes
condition: heat gently
reagents: solution with Cu2+ ions
observation: Cu2+ ions reduced to CuO (red ppt)
(& aldehydes oxidised to carboxylic acids)

30
Q

what compound could be tested with tollen’s reagent? state the conditions, reagents & observation.

A

aldehydes
condition: heat gently
reagents: aq, NH3 + AgNO3 -> complex ion [Ag(NH3)2]+
observation: silver mirror forms as Ag+ (aq) reduced to Ag(s))
(& aldehydes oxidised to carboxylic acids)

31
Q

what is the reagents & conditions of reduction of carbonyls?

A

reagents: LiAlH4 in dry ether / reduction agent
conditions: room temp. & Pa

32
Q

what would aldehydes & ketones be reduced to?

A

aldehyde: primary alcohols
ketones: secondary alcohols

33
Q

what are formed with nucleophillic addition of carbonyls?

A

hydroxynitriles

34
Q

what are the reagents & conditions of nucleophillic addition of carbonyls? draw the mechanism.

A

reagent: HCN in presence of KCN
conditions: room temp. & Pa

35
Q

what is the iodoform test specifically for?

A

carbonyls with methyl group attached next to C=O (ethanal / methyl ketones)

36
Q

what are the reagents & conditions of the iodoform test?

A

reagents - I2 with NaOH (alkali)
conditions - warm gently

37
Q

what is formed in the iodoform test? state the formula and the observations.

A

CHI3, triiodomethane
yellow ppt