10. Addition Reactions

Show what products you would expect from the following metathesis reactions, using the Schrock or Grubbs catalysts.

(a)

Synthesize the following molecules beginning with only organic molecules containing three carbons or fewer.

(g)

Using any necessary inorganic reagents, show how you would convert acetylene and isobutyl bromide to

(a) meso-2,7-dimethyloctane-4,5-diol, (CH₃)₂CHCH₂CH(OH)CH(OH)CH₂CH(CH₃)₂.

Predict the products formed when CH₃CH₂–C≡C:^–Na⁺ reacts with the following compounds.

a. ethyl bromide

b. tert-butyl bromide

c. formaldehyde

Show how you would accomplish the following synthetic conversions.

c. 1-methylcyclopentanol → 2-chloro-1-methylcyclopentanol

Problem-Solving Hint: The opening of a halonium ion is driven by its electrophilic nature. The weak nucleophile attacks the carbon bearing more positive charge.

Using 1,2-dimethylcyclohexene as your starting material, show how you would synthesize the following compounds. (Once you have shown how to synthesize a compound, you may use it as the starting material in any later parts of this problem.) If a chiral product is shown, assume that it is part of a racemic mixture.

(h)

Show what products you would expect from the following metathesis reactions, using the Schrock or Grubbs catalysts.

(c)

Show how you might use olefin metathesis to assemble the following alkenes from smaller units:

(a)

(b)

Starting with ethyne, describe how the following compounds can be synthesized:

a. (3S,4R)-4-bromo-3-hexanol and (3R,4S)-4-bromo-3-hexanol