Exam 18: Ethers and Epoxides;thiols and Sulfides

Draw: 1-isopropoxycyclopentene

Exhibit 18-3 Consider the data below to answer the following question(s). ​ Epoxides are synthesized industrially in one step by silver oxide air oxidation of ethylene and on a laboratory scale in one step by treating an alkene with m-chloroperoxybenzoic acid.An alternative two-step process converts alkenes to halohydrins,which are converted by treatment with base to epoxides. ​ -Refer to Exhibit 18-3.The synthesis of epoxides by base treatment of halohydrins is an example of an intramolecular:

Draw: 3-methyl-1-butanethiol

Which of the following will undergo rearrangement upon heating?

Exhibit 18-1 Consider the reaction below to answer the following question(s). -Refer to Exhibit 18-1.Alternatively,cyclopentyl methyl ether may be synthesized from cyclopentene.Outline a synthesis of cyclopentyl methyl ether from cyclopentene.

Choose the best reagent for carrying out the following reactions from the list below.Place the letter of the reagent(s) in the box over the reaction arrow.Use only one letter per box. A. NaH,then CH₃I B. NaOCH₃,CH₃OH C. m-ClC₆H₄CO₃H D. CH₃MgBr in ether,then H₃O⁺ E. warm H₂SO₄/H₂O F. Hg(O₂CCF₃)₂,CH₃OH G. H₂/Pd H. PCC,CH₂Cl₂ I. Cl₂,H₂O J. LiAlH₄ in ether,then H₃O⁺

Draw: diethyl ether

Draw: 12-crown-4

When 1,2-epoxypropane is treated with sodium ethoxide in ethanol 1-ethoxy-2-propanol is the major product while only a trace amount of 2-ethoxy-1-propanol is produced.Explain these results based on the reaction mechanism.

Name:

Consider the following species.Atoms other than carbon and hydrogen are labeled. Which of the following would be produced upon treatment with I₂?

Exhibit 18-2 Consider the data below to answer the following question(s). Acetals are a special class of ethers which have two ether linkages at a single carbon.Tetrahydropyranyl ethers are acetals that are easily cleaved with mild aqueous acids at room temperature to yield alcohols. -Refer to Exhibit 18-2.Draw arrows showing the electron flow for this reaction on the structures provided below.

Show how the ether below could be prepared from toluene and any other necessary reagents.Show all reagents and all intermediate structures.

Draw the structure of the ether that could be used to produce the following compound.

Although not always evident in an IR spectrum,which peak in the IR spectrum below might be due to the C-O stretch of an ether?

Draw: cyclopropyl ethyl sulfide

Name:

The following is the proton NMR of a symmetrical alkyl ether.Which peak is most likely due to the protons adjacent to the ether oxygen atom?

Predict the product of the following reaction.

Write the complete stepwise mechanism for the reaction below.Show all electron flow with arrows and draw all intermediate structures.