After reading this chapter and completing ALL the exercises, a student can be able to
- predict relative boiling points and solubilities of ethers (refer to section 15.1)
- explain how ether solvents stabilize electrophilic reagents (refer to section 15.1)
- determine the structures of ethers from their spectra, and explain their characteristic absorptions and fragmentations (refer to section 15.2)
- devise efficient laboratory synthesis of ethers and epoxides, including:
a) Williamson ether synthesis (refer to section 15.3)
b) alkoximercuration-demercuration (refer to section 15.4)
c) peroxyacid epoxidation (refer to Chapter 9 section 12)
d) base-promoted cyclization of halohydrins (refer to section 15.7)
- predict the products or reactions of ethers and epoxides, including:
a) acidic cleavage of ethers (refer to section 15.5)
b) opening of epoxides (refer to section 15.8)
c) reactions of epoxides with organometallic reagents (refer to section 15.10)
- explain how Crown ethers solvate metal cations (refer to section 15.10)
- explain the reaction of epoxy monomers to form the adhesive resin (refer to section 15.11)
- describe the structure and reactive of sulfides (refer to section 15.12)
- use your knowledge of chemical reactivity to propose mechanisms and products for similar reactions you have never seen before (chapters to date)
- propose multiple-step syntheses using all of the reactions studied through this chapter (chapters to date)
Please note: IUPAC nomenclature and important common names of alcohols were explained in Chapter 3.
- 15.1: Physical Properties of Ethers
- Ethers are weakly polar at the carbon oxygen bonds. The size and structure of the carbon chains bonded to the oxygen atoms influence the physical properties as well.
- 15.2: Spectroscopy of Ethers
- Ethers can be identified by the C-O stretch in the IR spectrum and the downfield shift of hydrogens in the proton NMR spectrum with a corresponding shift for the carbons in C-13 NMR.
- 15.3: The Williamson Ether Synthesis
- The Williamson Ether Synthesis proceeds by an SN2 reaction of an alkoxide nucleophile with an alkyl halide.
- 15.4: Alkoxymercuration-Demercuration Synthesis of Ethers
- Alkoxymercuration is a stereospecific, regioselective electrophilic addition reaction because there are no carbocation rearrangements due to stabilization of the reactive intermediate. The Markovnikov products are reliably synthesized by this pathway.
- 15.5: Acidic Cleavage of Ethers
- The most common reaction of ethers is cleavage of the C–O bond by strong acids.
- 15.6: Autoxidation of Ethers
- Careful handling of ethers is required to avoid potentially explosive situations.
- 15.7: Synthesis of Epoxides
- Epoxides (also known as oxiranes) are three-membered ring structures in which one of the vertices is an oxygen and the other two are carbons. Epoxides are useful reactants for building longer carbon chains with Grignard reagents.
- 15.8: Opening of Epoxides
- The opening of expoxides is a regioselective reaction depending on the structure of the epoxide and reaction conditions. The stereochemistry of the products produced by the different reactions is also discussed.
- 15.9: Reactions of Epoxides with Grignard and Organolithium Reagents
- Grignard reactions with ethylene oxide produce a primary alcohol containing two more carbon atoms than the original Grignard reagent.
- 15.10: Crown Ethers
- A “crown ether ” is a cyclic ether containing several (i.e., 4, 5, 6 or more) oxygen atoms. Crown ethers are notable because they can dissolve ionic compounds by solvating the cation.
- 15.11: Epoxy Resins - The Advent of Modern Glues
- Epoxy resins are a useful class of adhesives.
- 15.12: Thioethers (Sulfides) and Silyl Ethers
- Thiols and sulfides are the "sulfur equivalent" of alcohols and ethers.
- 15.13: Additional Exercises
- This section has additional exercises for the key learning objectives of the chapter.
- 15.14: Solutions to Additional Exercises
- This section has the solutions to the additional exercises from the previous section.