CHE 3332 – Organic Chemistry 2 – Spring 2021 Week 15 Resource

The last virtual group tutoring for this class will be Tuesday 4/27 from 6-7 pm so definitely attend! You can reserve your spot by making an appointment at www.Baylor.edu/Tutoring. This

is the final resource for the spring 2021 semester. It reviews the major topics from the second half of the semester. I hope that the organic chemistry II resources I shared with you this

semester were helpful and efficient in addressing your academic needs. All prior resources can also be found on the tutoring website.

Keywords: ketone, aldehyde, carboxylic acid derivative, Wittig, enolate, aldol, amine

Ch 20: Ketones & Aldehydes Acetal & Ketal Formation – A ketone makes a ketal, and an aldehyde makes an acetal. Two acids can be used in the formation: TSOH or H2SO4.

Imine Formation – A ketone reacts with a primary amine (one R group bonded to nitrogen) to make an imine.

Enamine Formation – A ketone reacts with a secondary amine (two R groups bonded to nitrogen) to make an enamine.

Wolff-Kishner Reduction – A hydrazone is reduced to an alkane. This is under basic conditions, with either KOH, KOt, or KOt-Bu as a reagent.

Hydrogen Nucleophilic Reactions – A ketone is reduced to an alcohol. This can be done with two different sets of reagents.

Wittig Reaction – A ketone/aldehyde reacts with a phosphorous ylide to make an alkene.

Baeyer-Villiger Oxidation – A ketone/aldehyde reacts with peracid (mCPBA or RCO3H) to make an ester. When the ketone is unsymmetrical, the more substituted group moves on to the oxygen:

Practice Questions:

1. Why are carbonyls (like aldehydes & ketones) so reactive?

2. Name this reaction & complete it:

3. Name this reaction & complete it:

Ch 21: Carboxylic Acid Derivatives Carboxylic Acids – These are the main reactions to make carboxylic acids.

1. Ozonolysis of alkynes 2. Oxidation of primary alcohol

3. Oxidation at benzylic position 4. Hydrolysis of nitriles

5. Carboxylation of Grignards Reaction of Carboxylic Acids – Reduction with LAH or BH3. LAH is very powerful and reduces everything; BH3 is more selective and only reduces carboxylic acids.

Practice Question:

4. Propose a synthesis:

Ch 22: Enols & Enolates The alpha-carbon can only act as a nucleophile if the carbonyl is in enol or enolate reactive form. Enols are made either through acid or base tautomerization. Enolates are more reactive than enols because they’re charged. You need a strong base to make an enolate like EtO or LDA.

Aldol Condensation – An aldehyde treated with base reacts with a second aldehyde to make an aldol.

Claisen Condensation – Esters react via their enolate. The ester has to have 2 alpha-protons to react. The base OR- must match the original ester.

Practice Questions: predict the products

5. 6.

Ch 23: Amines Reductive Amination to Make an Amine – A ketone/aldehyde can react with a variably substituted nitrogen group to make any kind of amine.

Amine to Amide – Acylate an amine with an acid chloride to make an amide (carboxylic acid derivative).

Practice Question: 7. How can this be made with reductive amination?

Answers: Notes & questions sourced from Wiley Organic Chemistry Second Semester textbook.

1. They have a dipole moment due to resonance.

2. Ketal formation

3. Enamine formation

4.

5.

6.

7.