Download Chap Thirteen: Alcohols

CHAPTER THIRTEEN: STRUCTURE AND SYNTHESIS OF ALCOHOLS
1. Structure/ Properties
a. Nomenclature
b. Relative Boiling points, solubility: hydrogen bonding
c. Acid/Base behavior
i. pKa of MeOH ≈ 16
ii. Acidity trends with branching near C-OH: branching hinders anion
solvation
iii. Basicity of neutral alcohol (pKb(A-) = 14.0 - pKa(HA))
iv. Basicity of alkoxide ion
v. Formation of alkoxide ion by reaction of alcohols with Na° or K°
2. Preparation of Alcohols
a. 1° alcohols from 1° Alkyl Halides with hydroxide (SN2, review)
b. Vicinal Diols from anti-addition of water to Epoxides under acidic or basic
conditions (review) or from oxidation of alkenes with OsO4 (review)
c. Via Grignard RMgX or RLi
i. Formation of Grignard or Alkyl Lithium from alkyl halides
ii. reaction with Ketones and Aldehydes
iii. reaction with acid chlorides or esters (double addition)
iv. reaction with epoxides (Anti stereoselective; SN2-like regioselectivity)
v. Side reactions with acidic compounds
d. Via reduction of carbonyls or epoxides with Hydride Reducing reagents
i. Reduction of Ketones, Aldehydes and Epoxides with either NaBH4 or
LiAlH4
ii. Reduction of Esters and Carboxylic Acids with LiAlH4 only
LEARNING OUTCOMES:
 Understand the formation of alcohols through use of organometallics in carboncarbon bond forming reactions with electrophiles
 Predict the stereochemistry and optical activity of a product from an understanding of
its mechanism of formation.
 Propose a reaction or sequence of reactions to produce a target alcohol in high yield.
 Predict the relative acidity of alcohols within a functional group class and compared
to other functional groups.
 Predict the relative boiling points of alcohols within a functional group class and
compared to other functional groups.
 Recognize structural features of a molecule that are key to its stability and reactivity.
SAMPLE EXAM PROBLEMS:
1. Draw the product of 3-(2-bromopropyl)-6,6-dimethylheptan-2-ol reacting with
2. Give the major organic product of the following reaction and include all
stereoisomers formed: