Green Oxidation Lab #1

What is the purpose of this experiment?

To oxidize a primary alcohol into an aldehyde using a green method

What is being oxidized in this lab?

Benzyl alcohol

What is the product formed?

Benzaldehyde

What makes this reaction "green"?

Uses oxygen, less toxic, less waste

Why avoid traditional oxidizing agents?

They are toxic and produce harmful waste

What is a catalyst?

Speeds up reaction without being used up

What does a catalyst lower?

Activation energy

What metal is used in the catalyst system?

Copper (CuBr)

What is TEMPO?

A stable organic radical used in oxidation

What is the role of 2,2'-bipyridine (bpy)?

Ligand for copper

What is NMI used for?

Helps activate the catalyst system

What is the oxidizing agent in this reaction?

Oxygen (O2 from air)

What happens to benzyl alcohol?

It is oxidized to benzaldehyde

What is produced along with benzaldehyde?

Water (H2O)

What gets reduced in the reaction?

Cu(II)

How do you know the reaction is working?

Color change occurs

What color change indicates progress?

Red/brown to green

When is the reaction complete?

When color change stabilizes

Why use a separatory funnel?

To separate organic and aqueous layers

Which layer contains the product?

Organic layer

Why add MgSO4?

To dry the organic layer

Why evaporate the solvent?

To isolate the product

What confirms aldehyde formation in IR?

C=O peak around 1700 cm^-1

What indicates over-oxidation in IR?

Broad O-H and C=O (carboxylic acid)

Why wear gloves and goggles?

Chemicals are toxic and corrosive

Why is food not allowed in lab?

To prevent contamination

Which solvents are flammable?

Acetone and pentane

What is the formula to convert mmol to grams?

mass = mmol × (MW / 1000)

How many grams are in 2.5 mmol of benzyl alcohol (MW 108.14)?

0.27 g

What makes an oxidizing agent green?

Non-toxic and safe by-products

Why is oxygen a good oxidizing agent?

It is clean and produces water

What evidence in 1H NMR shows over-oxidation?

Loss of aldehyde proton peak (~9-10 ppm) and appearance of broad carboxylic acid proton (~10-13 ppm)

What evidence in IR shows over-oxidation?

Broad O-H stretch (~2500-3300 cm^-1) and strong C=O (~1700 cm^-1) of carboxylic acid

What is the key reaction to form compound A from benzaldehyde?

Imine (Schiff base) formation

What reagents are needed to form an imine?

Aldehyde + amine

What functional group is formed in compound A?

C=N (imine)

What reaction type forms the C=N bond?

Condensation reaction (loss of water)

How can 4-bromobenzaldehyde be modified to add another aromatic group?

Suzuki coupling or other cross-coupling reaction

What type of reaction is used to connect aromatic rings?

Palladium-catalyzed coupling (Suzuki reaction)

What is the first step in synthesizing compound A?

Cross-coupling to build the biphenyl structure

What is the second step?

Imine formation with amine

How does this reaction follow green chemistry principles?

Uses catalytic system instead of stoichiometric reagents

What green chemistry principle involves reducing waste?

Prevention of waste

What green chemistry principle involves safer chemicals?

Less hazardous synthesis

What green chemistry principle involves catalysts?

Catalysis

What green chemistry principle involves using oxygen?

Use of safer reagents and renewable inputs

Why is this reaction environmentally friendly?

Produces minimal waste and uses oxygen from air