Review the Alcohol module in ORGO.

1. How many grams of K2Cr2O7 are required to oxidize 10.0 g of cyclohexanol to

cyclohexanone in aqueous sulfuric acid? Review redox reactions from general

chemistry. Also see section 10-2a in your text. Show the balanced equation and your calculations.

2. When CD2=CHCH2OH is treated with HCl, both CD2=CHCH2Cl and CH2=CHCD2Cl

are formed. Explain.

3. Ozonolysis of one mole of (E)- or (Z)-butene followed by reduction with dimethyl

sulfide produces two moles of acetaldehyde and dimethylsulfoxide [(CH3)2S --->

(CH3)2S->O]. The conversion of (E)- or (Z)-butene to two moles of acetaldehyde can

also be achieved with catalytic OsO4 (-2e) and two moles of periodic acid (HIO4; -2e).

Show the steps for each pathway. Ozonolysis itself is a 6-electron oxidation. How can

you tell?

4. 2-Methyl-2-propanol forms an 2-chloro-2-methylpropane with concentrated

hydrochloric acid faster than 1-butanol forms 1-chlorobutane under the same

conditions. Explain

5. Organic synthesis is the process of making more complex structures from simpler ones.

Usually more than one chemical transformation is required. Show how the ketone, 3-

hexanone, can be prepared from ethylene as the only carbon source. All reagents are at

your disposal.

6. The reagent CrO3.2pyr. in problem 3 of the Alcohol module of ORGO serves the same

function as PCC (pg. 436). It oxidizes primary alcohols to aldehydes. Show how the

ester ethyl acetate may also be formed in the oxidation of ethanol to acetaldehyde.

7. When (±)-CH3CDHOH is oxidized with a less than stoichiometric quantity of CrO3.2pyr., CH3CHO

is the minor product and CH3CDO is the major one. Cleavage of the C-H bond is the rate-limiting step

and not chromate ester formation. Explain and draw a reaction co-ordinate diagram.

8. When (S)-CH3CDHOH is oxidized to acetaldehyde by the enzyme alcohol dehydrogenase

and the coenzyme NAD+ (pg. 481), CH3CDO is formed. How is this result possible in light

of the result in #7? What is the product of oxidation of the (R)-enantiomer?

Which oxidation might you expect to be faster as a result of the information in #7?