In addition to the specific and more detailed goals listed for each topic we study, we have overall goals, things that we want to take away with us from the course. The individual study topics and goals are simply a means to the more general end. We want to:

• Understand what organic chemistry is: what organic chemists do, and think about, and why this is important in our everyday lives;

• Improve our tools for thinking about the physical world;

• Improve our problem solving skills, learning methodology that works with many kinds of problems;

• Learn to communicate scientific information clearly and accurately, with both words and pictures.

Chapter 9

When you have finished this Chapter you should:

• Be able to write equations for the preparation of alkynes by:
  • dehydrohalogenation

  • S_N2 reactions of simpler terminal alkynes

• Be able to write product structures, including stereochemistry, for reaction of alkynes with:

  • HX

  • Cl₂, Br₂

  • Hg⁺⁺ / H₂O

  • R₂BH, H₂O₂, OH^-

  • H₂ and Lindlar Pd

  • Na / NH₃

• Be able to write mechanisms that account for the regio- and stereochemistry of the preceeding reactions

Chapter 10

When you have finished this Chapter you should

• Be able to recognize conjugation in organic molecules and draw the underlying systems of p- orbitals

• Be able to explain why conjugations stabilizes organic species

• Be able to write products for two kinds of reactions of conjugated dienes:
  • electrophilic addition (1,2- vs 1,4-)

  • cycloaddition (the Diels-Alder reaction)

• Be able to analyze Diels-Alder reactions retrosynthetically (that is, work out from the structure of the product the structures of the reactants)

• Be able to use frontier orbital theory (HOMO-LUMO interactions) to explain why the Diels-Alder reaction proceeds whereas other very similar-looking cycloadditons don't

Chapter 11

Finally, we begin to explain why we have been ignoring those "double bonds" in benzene!

When you finish this Chapter, you should

• Be able to describe how benzene is different from simple conjugated polyenes

• Be able to explain that difference using MO theory

• Be able to identify other species with benzene-like properties by using:
  • Huckel's 4n + 2 Rule

  • Frost's Circles

• Be able to explain the special reactivity of alkyl side chains on benzene rings

• Be able to write equations for the reactions of alkyl benzenes
  • Free radical substitution

  • Oxidation to carboxylic acids

• Be able to name simple benzene derivatives

Chapter 12

We are now largely finished presenting the concepts we need to understand organic reactions. Each chapter from now on contains a dozen or more new reactions. We need to use our grounding in MO theory and general knowledge to understand why these reactions occur as they do, and then learn to use the reactions in combination to produce new molecules. Chapter 12 starts this task with a survey of the reactions of aromatic rings. When you have finished this Chapter you should:

• Be able to write the generic mechanism for electrophilic substitution as applied to:
  • H/D exchange using D₂SO₄

  • Sulfonation

  • Nitration

  • Halogenation

  • Friedel-Crafts alkylation and acylation

  • A short summary of these reactions is HERE

• Be able to describe electrophilic attack in filled-empty orbital terms

• Be able to explain and predict how groups attached to a benzene ring influence
  • the reactivity of the ring toward electrophiles

  • the site of electrophilic attack

  Here's some help in learning to write resonance structures, which you need to be able to do to understand substituent effects.

• Be able to use the preceding information to write, retrosynthetically, multi-step syntheses of substituted benzenes.

Chapter 14

When we have finished this Chapter, you should be able to:

• Write equations describing the preparation of organometallic reagents based on
  • Li

  • Mg

  • Cu

  • Zn

• Explain the connection between the relative electronegativities of carbon and these metals and the kinds of reactions they undergo

• Describe the relationships between the various oxidation states of carbon

  (Consult the CHART of carbon oxidation states)

• Write equations showing how organometallic reagents may be used to prepare alcohols from aldehydes and ketones

• Write equations showing the preparation of alkanes using cuprolithium reagents

• Write equations showing how cyclopropanes may be prepared from alkenes and carbenes

• Use all of the new reactions retrosynthetically

Chapter 15

We will ignore sections 15.7 - 15.9.

This Chapter provides a complete description of the preparation and reactions of alcohols. You should begin your work by creating your own review, looking back through your notes and the text, of

• All reactions that produce alcohols

• All reactions of alcohols

We then continue with some new preparations of alcohols. When we finish, you should:

• Be able to write equations for the preparation of alcohols by
  • reduction of aldehydes and ketones with NaBH₄ or LiAlH₄

  • reaction of oxiranes with Grignard reagents or cuprolithium reagents

  • reaction of alkenes with OsO₄

You should also be able to write equations for

• Oxidation of alcohols to aldehydes, ketones, and carboxylic acids, using various chromium-based reagents

• The oxidative cleavage of vicinal diols by HIO₄

• Be able to write examples of the formation of thiols and sulfides by S_N2 reactions of alkyl halides with HS^- and RS^-

• Determine the structure of alcohols from spectroscopic data

• Predict the appearance of the ¹H and ¹³C spectra of alchols from their structure

For fun, we will take a short look at Mother Nature's way of oxidizing alcohols and at some of her more interesting sulfur compounds.

Chapter 16

When you have finished this chapter you should be able to:

• Write reactions for the preparation of ethers by:
  • the Williamson ether systhesis (S_N2)

  • alkoxymercuration

• Use a retrosynthetic analysis to select the best methodology for preparing a specific ether

• Write equations for the preparation of oxiranes using two methods discussed last semester

• Write mechanisms showing how the acid-catalyzed cleavage of ethers follows the S_N1/S_N2 pathway described last semester for alcohols

• Write equations showing how oxiranes can be open to substituted alcohols by reaction with various nucleophiles
  • Explain the regio- and stereoselectivity of these reactions

  • Do retrosynthetic analyses of the products of these reactions

• Write equations showing the acid-catalyzed ring opening of oxiranes to alcohols and diols
  • Explain the regio- and stereoselectivity of these reactions

Chapter 17

Chapter 17 is the first of two chapters (18 is the other) describing the chemistry of aldehydes and ketones. This chapter considers the reactivity of nucleophiles with the carbon-oxygen double bond.

When you have finished this Chapter, you should:

• Be able to describe the orbital structure of the C=O bond

• Be able to explain using either charge distribution or filled-empty (HOMO-LUMO) orbital theory why
  • nucleophiles attack the carbonyl carbon

  • electrophiles attack the carbonyl oxygen

• Be able to write products and mechanisms for the additions of
  • H₂O

  • CN^-

  • ROH

  • RNH₂ and R₂NH

  • Ph₃P=CHR (Wittig reagents)

  to the carbonyl.

• Be able to write reactions for the oxidation of ketones by peracids (the Baeyer-Villiger reaction)

• Be able to use spectroscopic and chemical information to work out structures of carbonyl compounds

Be sure also to review all reactions we have learned for the preparation of aldehydes and ketones.

Chapter 18

Chapter 18 presents a number of complicated-looking reactions in which nucleophiles derived from aldehydes and ketones do nucleophilic addition reactions with aldehydes and ketones. The reactions are called condensations, because usually a small molecule such as water is lost during the processes. Focus very hard on understanding the mechanisms of these reactions as a way of keeping straight what is happening!

When you have finished this Chapter you should:

• Be able to write mechanisms for both acid- and base-catalyzed enolization of aldehydes and ketones

• Be able to write examples of and mechanisms for some enol and enolate reactions:
  • isotopic exchange of a-hydrogens

  • racemization of aldehydes and ketones in which a-carbons are stereogenic centers

  • halogenation

  • alkylation

• Be able to write examples of and mechanisms for the aldol condensation, and be able to do retrosynthetic analyses of aldol products

• Be able to write examples of and mechanisms for the Michael addition reaction of a, b-unsaturated aldehydes and ketones, and do retrosynthetic analysis of Michael additions

• Be able to write examples of and mechanisms for Robinson annelations, which are combined Michael additions and aldol condensations, and do retrosynthetic analysis of Robinson products

Chapters 19 and 20

Chapter 19 is a relatively short chapter, introducing the chemistry of carboxylic acids. It includes some reactions that make more sense in Chapter 20. Hence, I am going to combine the two chapters, and move from one into the other without a break. Thus we will have all the nucleophilic acyl substitution chemistry on our organizing chart together in one place.

When you have finished these Chapters, you should

• Be able to explain how the weak acidity of carboxylic acids is related to their structure

• Be able to show how carboxylic acids can be prepared by:
  • oxidation of 1^o alcohols

  • carbonation of Grignard and lithium reagents

  • hydrolysis of nitriles

• Be able to write examples of and mechanisms for several examples of nucleophilic acyl substitution:
  • esterification of carboxylic acids and hydrolysis of esters

  • conversion of acids to acyl chlorides

  • interconversion of esters and amides

  • hydrolysis of amides

• Be able to write examples of the nucleophilic acyl substitution reactions of acyl chlorides with
  • lithium aluminum hydride, LiAlH₄

  • Grignard reagents, RMgX

  • LiAl(OtBu)₃H, lithium aluminum tri-t-butoxy hydride

  • cuprolithium reagents, R₂CuLi

  and be able to use these reactions in synthesis

• Be able to write examples of the reaction of carboxylic acids with:
  • lithium aluminum hydride, LiAlH₄

  • lithium reagents, RLi
  and be able to use these reactions in synthesis

• Be able to write examples of the reactions of esters with
  • lithium aluminum hydride, LiAlH₄

  • Grignard reagents, RMgX

  • diBAL-H, dibutyl aluminum hydride

  and use these reactions in synthesis

Chapters 21

We've reached the end! Congratulations!

This chapter introduces three new reactions, and briefly revisits one from Chapter 19.

When you have finished this chapter you should be able to:

• Be able to write equations for
  • the Claisen condensation and its intromolecular version, the Dieckmann condensation

  • the acetoacetic ester synthesis of ketones

  • the malonic ester synthesis of carboxylic acids

  and use these reactions retrosynthetically

• Write all steps of a mechanism for each of these reactions

Here is a brief review of most of the condensation chemistry in Chapters 19 and 21.