CHEM 2212 Lab Final

Spring 2026

Conversion of Carvone to Carvacrol is a ___ catalyzed reaction by ____

acid, 6M H2SO4

starting material, ending material, and catalyst/sovlent used in the conversion of carvone to carvacrol lab

R/S- carvone —-6M H2SO4 and heat—→ carvacrol ——————

carvone is a…

beta-alpha unsaturated ketone that is optically active

carvacrol is a…

phenol derivative that is optically inactive

is the conversion of carvone to carvacrol a thermodynamically favored reaction?

yes, because it is conducted in reflux and results in elimination

what is the driving force behind the tautomerization in the carvone to carvacrol lab?

• aromaticity

• resonance is highly stabilized and favored.

• delocalization of pi electrons and resonance stabilitization causes the atomatic system to release energy and drive the reaction forwards.

In the carvone to carvacrol lab, why has the equilibrium of this rapid interconversion shifted to the enol tautomer?

the ketone form is more stable than enol, the enol form predominations because that structure leads to aromatic ring formation (which is highly preferred).

what is the purpose of the ether extraction in the carvone to carvacrol.

diethyl ether is an ether that moves any carvacol remnants from the aqueous layer into the organic layer.

what is the purpose of the water wash in the carvone to carvacrol lab?

pull any water soluble impurities in the organic layer into the aqueous layer.

what is the purpose of the saturated sodium bicarbonate wash in the carvone to carvacrol?

• basification

• ether extract was washed with sodium bicarbonate (basic solution) to neutralize the acid and any acidic impurities in the organic layer.

what was the purpose of the brine wash in carvone to carvacrol lab?

• pre drying step that removes any residual chunks of water from the organic layer prior to the drying agent (sodium sulfate) which dries the product.

what is the drying agent in the carvone to carvacrol lab?

Sodium Sulfate (Na2SO4) removed via suction filtration

does the starting enantiomer matter in the carvone and carvacrol lab?

• no because, final product is achiral

what are the byproducts in the carvone to carvacrol lab from the sodium bicarbonate (NaHCO3) and sulfuric acid (H2SO4)

CO2 (g), Na2SO4, and H2O

what is the reducing agent in the reduction of an unknown Aldehyde/Ketone lab?

Sodium Borohydride (NaBH4) is gentle reducing agent

what is the starting material, reducing agent, solvent, and product in the reduction of an unknown ketone/aldehyde lab?

• starting material: unknown ketone/aldehyde

• reducing agent: sodium borohydride

• solvent: 95% ethanol

• product: primary or secondary alcohol

NaBH4 reacts ___ with ____ solvents to produce ___ gas at ____ temperature in the reduction of an unknown aldehyde/ketone lab.

slowly; protic; H2(g); room temperature

what does microwave heating do in the reduction of an unknown aldehyde/ketone lab?

• increases reaction rate

• dielectric heating excites the dipole moments in the polar molecules of ethanol.

what is the solvent in the reduction of an unknown aldehyde/ketone lab?

95% ethanol

What is the purpose of the water in the reaction in the reduction of an unknown aldehyde/ketone?

a washing agent to remove ethanol and borate salts from the organic later

in liquid-liquid extraction in the reduction of an aldehyde/ketone experiment?

• aqueous: borate salts & ethanol

• organic: newly formed OH

What is the drying agent in the reduction of an unknown aldehyde/ketone lab?

drying agent: MgSO4 (magnesium sulfate)

removed by gravity filtration w

what is the purpose of the rotary vap in the reduction of an aldehyde/ketone lab?

• isolated liquid/solid by removing the volatile extraction solvent (ethyl acetate)

• rotary vaps reduces the internal pressure allowing less heat needed & less thermal decomposition

how do impurities impact the melting point?

they broaden melting point ranges and depress their values.

would acetone by a more suitable solvent for the reduction of an unknown aldehyde/ketone?

• no, acetone is a ketone and would be reduced with NaBH4 as well.

  • solubility has less of an impact in determining the solvent suitability because the NaBH4 reacts with it.

what is the odizing agent in the oxidation of an unknown alcohol lab?

• NaOCl

• bleach = NaOCl + H2O

• “Green” oxidizing agent

what is the starting material, oxidizing agent, solvent, and product of the oxidaiton of an unknown alcohol lab?

• starting material: unknown alcohol

• oxidizing agent: HOCl (mild oxidizer)

• solvent: acetic acid

• product: ketone

what are the meaning of oxidation

1. add O atoms

2. Add other EN atoms

3. Decrease the # of C-H bonds

4. Increase bond order

5. loss of e-

what is the solvent in the oxidation of an unknown alcohol lab?

acetic acid

is the reaction endothermic or exothermic in the oxidation of an unknown alcohol lab?

exothermic

what are the two roles acetic acid play in the oxidation of an unknown alcohol experiment?

• catalyst - coverts NaOCl into HOCl (which is the actual active oxidizing species).

• solvent

Why do we add the bleach dropwise in the oxidation of an unknown alcohol lab?

we add the HOCl so the temperature doesn’t spike & side reactions don’t occur & volatile product isn’t lost.

What is the quenching agent in the oxidation of unknown alcohol lab?

Sodium Bisulfite

Why is KI starch paper used 2x in the oxidation of an unknown alcohol lab?

• 1st time: turn paper blue. Add more NaOCl (oxidizing agent) until it turns blue.

• 2nd time: keep paper white. Add more Sodium Bisulfite (Quenching agent) until the paper remains white.

Why was 6M NaOH added to the reaction mixture in the oxidaiton of an unknown alcohol lab?

• occurs after testing on KI Starch Paper

• to achieve a basic solution

• base neutralizes residual acetic acid so that product remains unionized and water soluble.

Why does quenching and base wash in the reaciton vessel occur before liquid-liquid extraction in the oxidation of an unknown alcohol lab?

• to neutralize the harsh environment caused by bleach and acetic acid

what is the extracting agent used in the liquid-liquid extraction step of the oxidation of an unknown alcohol lab?

• ethyl acetate - extract product in the separatory funnel

what are the two washing agents used in the oxidation of an unknown alcohol lab after ethyl acetate extraction?

1. DI water (washed organic layer from NaOH, Sodium Acettae, and Ethanol— polar impurities).

2. brine - “pre- drying agent” to remove excess water from the organic layer.

what is the drying agent used in the oxidation of an unknown alcohol lab?

• magnesium sulfate - removed by gravity filtration

how was the solvent and the extract seperated in the oxidation of an unknown alcohol lab?

• rotary evaporator

What does 4 + 2 cycloaddition mean in the diels-alder reaction lab?

the 4 pi electrons n the diene react with the 2 pi electrons in the dienophile.

what (if any) solvents/catalysts used in the diels alder reaction?

no solvents or catalysts are used (heat is not considered a catalyst)

what is the starting materials and product of the diels alder reaction?

starting materials: cyclopentadiene and unknown alkyne dienophile

product: bicyclic diels-alder product

Diels alder reaction occurs in one step. What is this called?

concerted

How does temperature affect the diels alder reaction?

• moderate/room temperature favors the forward Diels Alder Reaction

• high temperatures (~170 degrees) favors the retro Diels Alder

How does EWG/EDG impact the diels alder reaction

• increase number of EWG near the DIENOPHILE results in a faster reaction and a higher yield

• increase number of EDF near the DIENE results in a faster reaction and a higher yield.

In what formation does the diene have to be in for the diels alder reaction?

The diene must be in a s-cis formation

What occurs at room temperature for the diels alder reaction?

• dimerization

  • cyclopentadiene reacts with itself

how do you reverse dimerization in the diels alder reaction?

• heat the cyclopentadiene to ~168 degrees C to initiate the retro diels alder reaction.

what are the 2 reasons that cyclopentadiene is added dropwise to the reaction flask in the diels alder reaction?

1. the reaction is exothermic and adding al of the diene at once can spike the solution temperature and cause the pentadiene to be boiled away, causing a low yield.

2. adding the diene dropwise allows more dienophile to be present instead of the diene, forcing the reaction to occur with the dienophile instead of dimerizing.

Friedel Crafts Alkylation is a ____ Reaction. What does that mean?

• Electrophilic aromatic substitution (EAS)

  • when a H adjacent to an aromatic system is replaced with an Electrophile

How does EDG impact EAS reactions in the friedel crafts alkylation experiment?

• EDG causes the reaction to proceed quickly

What is benzene’s role in the friedel crafts alkylation lab? And what does it cause?

• benzene behaves as a nucleophile creating a resonance stabilized carbocation intermediate.

• causes E1 elimination to occur.

what are the starting materials, solvents, catalysts, and products of the friedel crafts alkylation lab?

• starting material

  • 2 equivalents of the unknown tertiary alcohol

  • 1,4-dimethoxybenzene

• solvent: acetic acid

• catalyst: sulfuric acid

• product: dialkylated 1,4 dimethoxybenzen

what are the two ways to generate a Nucleophile in the friedel crafts alkylation lab? Which one are we using in lab?

1. alkyl halide + Lewis Acid (AlCl3)

2. protonation of the secondary/tertiary alcohol via a bronsted acid catalyst (H2SO4)

what were the conditions for the reaction for the friedel crafts alkylation lab?

1. the EM Flask was chilled to add the acid catalyst (H2SO4) then reacted at room temperatre

how was the reaction quenched in the friedel crafts alkylation lab?

• ice cold water was the quenching agent which caused a white precipitate to form

how was the white precipitae filtrated in the fridel crafts alkylation lab?

• white precipitate was suction filtered and rinsed with DI water

what is the purpose of ethanol and methanol in the friedel crafts alkylation lab?

ethanol: rinsing agent

methanol: recyrstillation agent ot purify precipitate

What is the starting materials, reagents and product of the witting reaction?

• starting material:

  • benzyltriphenylphosphonium chloride

  • 9-anthranaldehyde

• reagents:

  • sodium hydroxide (NaOH)

• products: 9-(2-phenylethenyl)anthracene

Why is NaOH added dropwise in the wittig reaction?

to reduce the amount of side reactions that can occur.

why is the witting reaction mixture non-homogenous?

• aldehyde is hydrophobic

• ylide is hydrophillic (if you can’t remember this is easy to remember because ylide is a charged molecule)

what molecules are preferred for ylide formation and what reaction mechanism?

• primary or secondary alkyl halides, benzylic or allylic alkyl halides are preferred as well.

• reaction proceeds with an SN2 mechanism (strong base required for this to occur)

why must the wittig reaction cosntantly be stirred?

• increase the interaction surface area between the hydrophobic aldehyde and the hydrophillic ylide.

what is the drying agent for the wittig reaction?

calcium chloride (which is removed via decanting)

what is simple distillation and what experiment is it used in?

simple distillation is used in the wittig reaction and removes ehtyl acetate (organic solvent). It seperates 2 miscible mixture of liquids that have a boiling point difference greater than 100 degrees C

What is the organic solvent and the recrystallization solvent in the wittig reaction? When is it added?

1. drying agent calcium chloride is added - removed via decanting

2. organic solvent ethyl acetate is added - removed via simple distillation

3. recrystallization solvent 1-propanol is added - purifies solid

How are fischer esterification products typically synthesized?

carboxylic acid + alcohol

what are the starting materials, catalyst, solvent, and product for the fischer esterification lab?

• starting materials:

  • acetic acid

  • unknown primary alcohol

• catalyst:

  • sulfuric acid

• solvent:

  • acetic acid

• product:

  • ester

how do all fischer esterification reactions proceed? and what does that mean?

• microscale reversibility

  • forward and reverse pathways in the mechanism are identifcal

what was the purpose of the microwave heating in the fischer esterification lab?

• dielectric heating

• allows reaction time to decrease under constant temperature and pressure

what lab does le chatelier’s principle apply to and in what 2 ways can it be employed?

• fischer esterification lab

1. excess starting material (carboxylic acid)

2. remove water as it forms (what our experiment does)

what are the washing agents for the fischer esterification lab? What are their purpose?

1. water: organic layer to remove aquous imputiries

2. sodium bicarbonatie: basification and to neutralize remaining acetic acid/sulfuric acid—CO2 is released as a gas

3. brine: pre drying agent that removes excess water

what is the drying agent in the fischer esterification lab?

• sodium sulfate (Na2SO4) (removed via decanting)

What are the starting materials, catalyst, solvent, and products of the amide synthesis?

• starting materials:

  • acetic anhydride

  • unknown primary amine

• catalyst:

  • Aluminum Oxide

• Solvent:

  • acetic anhydride—basic conditions

• products

  • amide acetate

what type of reaction is amide syntheiss between CAD and primary/secondary amines?

nucleophilic substitution reaction

What extraction agent is used in amide synthesis?

Ethyl acetate: extracts product from reaction mixture since only the product is soluble.

what does gravity filtration seperate in the amide synthesis lab?

ehtyl acetae and precipitate——any excess ethyl acetate gets removed via heat, leaving the final, solid product.

is there a drying agent used in the amide synthesis lab?

no

What are the starting materials, solvent, solution, and product in the aldol condensation lab?

• starting materials:

  • acetone (serves as a nucleophile)

  • 2 equivalents unknown aldehyde (serves as a electrophile)

• solvent:

  • 95% ethanol

• solution:

  • aq NaOH

• product:

  • alpha, beta unsaturated ketone

What was produced as the reaction proceeded in the aldol condensation lab?

• white/yellow precipitate

  • reaction vial was placed in a ice bath afterwards to assist in crystallization

how many times was suction filtration used in the aldol condenation lab and what for?

1. crystals were collected via suction filtration post ice bath.

2. recrystallization from ethanol to purify the final product product

what was the washing agent to neutralize ___ in the reaction mixture (aldol condensation lab)?

• washing agent: ice cold water

• aimed to neutralize residual sodium hydroxide

in what two labs are there 2 equivalents of starting material (therefore balanced chemical equation does not have a 1:1:1:1 ratio)

1. Friedel Crafts Alkylation

2. aldol condensation