{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Chapter 11 Notes - Chapter11 AlcoholsandEthers...

Info iconThis preview shows pages 1–10. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 11 Alcohols and Ethers
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Nomenclature and Structure (1) Nomenclature of Alcohols: previously discussed; see Sec. 4.3F. (2) Nomenclature of Ethers: (a) Common Names ‐ The groups attached to the oxygen are listed in alphabetical order. (b) IUPAC Names ‐ Ethers are named as having an alkoxyl substituent on the main chain.
Background image of page 2
Cyclic ethers can be named using the prefix oxa‐. Three‐membered ring ethers can be called oxiranes. Four‐ membered ring ethers can be called oxetanes. Physical Properties of Alcohols and Ethers: Ether boiling points are roughly comparable to hydrocarbons of the same molecular weight. Molecules of ethers cannot hydrogen bond to each other. Alcohols have considerably higher boiling points. Molecules of alcohols hydrogen bond to each other. Both alcohols and ethers can hydrogen bond to water and have similar solubilities in water. Diethyl ether and 1‐butanol have solubilites of about 8 g per 100 mL in water.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Synthesis of Alcohols from Alkenes (1) Acid‐Catalyzed Hydration of Alkenes: This is a reversible reaction with Markovnikov regioselectivity. (2) Oxymercuration‐demercuration : This is a Markovnikov addition which occurs without rearrangement.
Background image of page 4
(3) Hydroboration‐Oxidation: This addition reaction occurs with anti‐Markovnikov regiochemistry and syn stereochemistry.
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
In Class Problem: Draw the structure of the major product(s) you would expect when the following alkene is subjected to (a) acid‐catalyzed hydration, (b) hydration by oxymercuration‐demercuration, and (c) hydration by hydroboration‐oxidation.
Background image of page 6
Alcohols as Acids Alcohols have acidities similar to water. Sterically hindered alcohols such as tert ‐butyl alcohol are less acidic (have higher pKa values). Why?: The conjugate base is not well solvated and so is not as stable. Alcohols are stronger acids than terminal alkynes and primary or secondary amines. An alkoxide can be prepared by the reaction of an alcohol with sodium or potassium metal.
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Conversion of Alcohols into Alkyl Halides Hydroxyl groups are poor leaving groups, and as such, are often converted to a group that can depart as a weak base; hydroxyl groups are converted to good leaving groups. Three general methods exist for conversion of alcohols to alkyl halides, depending on the classification of the alcohol and the halogen desired. Reaction can occur with hydrogen halides, phosphorus tribromide, or thionyl chloride.
Background image of page 8
Alkyl Halides from the Reaction of Alcohols with Hydrogen Halides The order of reactivity is as follows: HI > HBr > HCl > HF. Type of alcohol 3 o > 2 o > 1 o < methyl. Mechanism of the Reaction of Alcohols with HX: S N 1 mechanism for 3 o , 2 o , allylic and benzylic alcohols. These reactions are prone to carbocation rearrangements.
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 10
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}