[PHA6115 lab] Experiment 1

Question 1

Interaction of two or more chemical species to form a new product

Answer 1

Synthesis

Question 2

AKA Oil of Wintergreen

Answer 2

Methyl salicylate

Question 3

What are the uses of Methyl salicylate?

Answer 3

1. Topical analgesic - together with counterirritants, treat minor aches and pains in joints and muscles
2. Flavoring agent

Question 4

Distinct characteristic of Methyl salicylate

Answer 4

Minty odor

Question 5

AKA Acetylsalicylic acid

Answer 5

Aspirin (ASA)

Question 6

What are the uses of Acetylsalicylic acid?

Answer 6

1. Analgesic
2. Antipyretic
3. Anti-inflammatory

Question 7

[Reaction Mechanism of Different Class of Compounds]
Alkanes

Answer 7

Free-radical substitution

Question 8

[Reaction Mechanism of Different Class of Compounds]
Alkenes and Alkynes

Answer 8

Electrophilic addition

Question 9

[Reaction Mechanism of Different Class of Compounds]
Arenes

Answer 9

Electrophilic substitution

Question 10

[Reaction Mechanism of Different Class of Compounds]
Substituted Alkanes

Answer 10

Nucleophilic elimination/substitution

Question 11

[Reaction Mechanism of Different Class of Compounds]
Carbonyl compounds

Answer 11

Nucleophilic addition

Question 12

[Reaction Mechanism of Different Class of Compounds]
Carboxyl compounds

Answer 12

Nucleophilic acyl substitution

Question 13

Formulation for synthesis of Methyl salicylate

Answer 13

0.5 g salicylic and 3 mL of methanol

Question 14

Positive catalyst in the synthesis of Methyl salicylate

Answer 14

2 drops of sulfuric acid

Question 15

T or F: The drops of sulfuric acid should be added rapidly

Answer 15

False, it should be slowly (rapid = result to splattering, loss of product, contact with skin)

Question 16

Water bath formulation for synthesis of Methyl salicylate

Answer 16

70 degrees for 15 min

Question 17

Formulation for synthesis of Aspirin

Answer 17

2 g salicylic acid and 5 mL acetic anhydride

Question 18

How many drops of sulfuric acid for the synthesis of Aspirin?

Answer 18

5 drops

Question 19

Water bath formulation for synthesis of Aspirin

Answer 19

70-80 degrees for 20-30 mins

Question 20

When do we add more room temperature water?

Answer 20

Until a max of 40 drops or until cloud and aspirin crystals appear

Question 21

T or F: In the synthesis of aspirin, we rinse the test tube using ice cold water for 10 mins

Answer 21

True, because Aspirin has low solubility in cold water

Question 22

Is purification necessary when doing organic synthesis? Why?

Answer 22

Yes, because it is hard to perform characterization on impure products

Question 23

Examples of Purification Methods

Answer 23

1. Sublimation
2. Distillation
3. Chromatography
4. Recrystallization

Question 24

It involves the removal of unwanted materials and compound (impurities) and leave behind the pure compounds

Answer 24

Purification

Question 25

It involves the method to assess whether the desired compounds was indeed produced

Answer 25

Characterization

Question 26

T or F: IR spectroscopy is an example of a characterization technique

Answer 26

True

Question 27

What will happen if a sample with impurities is subjected immediately to IR analysis?

Answer 27

1. Peaks of impurities and peaks of the desired product may overlap 2. Unusual IR spectrum

Question 28

Methyl salicylate and Aspirin are both __________?

Answer 28

Esters of salicylic acid

Question 29

Reaction equation for synthesis of Methyl salicylate

Answer 29

Salicylic acid + Methanol <-> Methyl salicylate + Water

Question 30

Reaction equation for synthesis of Aspirin

Answer 30

Salicylic acid + Acetic anhydride -> Acetylsalicylic acid + Acetic acid

Question 31

Mechanism Review of Esterification

Answer 31

1. Protonation 2. Nucleophilic attack of alcohol 3. Proton transfer 4. Elimination of water 5. Deprotonation 6. Ester

Question 32

Maximum theoretical amount in grams of product that can be produced from the reaction

Answer 32

Theoretical Yield

Question 33

TY is dictated by

Answer 33

Limiting reagent

Question 34

T or F: The limiting reagent will be completely consumed after the reaction

Answer 34

True

Question 35

Characterization Techniques

Answer 35

1. Odor 2. Ferric chloride Test 3. Chromatography 4. FTIR

Question 36

[Characterization] Methyl salicylate has a minty odor

Answer 36

Odor

Question 37

[Characterization] A complexation reaction by adding 1% of ferric chloride solution to test the purity of the final product

Answer 37

Ferric chloride test

Question 38

[Characterization] Ferric chloride test complex goes from what color to what color?

Answer 38

Yellow to purple complex

Question 39

[Characterization] What solvent system is used for chromatography?

Answer 39

3:1 hexane to ethyl acetate