Test 1
Dr. Bachrach
CHEM 2319-2
2/12/14

Answer Key

1) Provide the IUPAC name for the following compounds.

a)

3,6-dimethyl-4-propyloctane

b)

cis-1-s-butyl-3-methylcyclohexane

c)

3,4,6-triethyloctane

d)

4-cyclobutyl-2-methylheptane

2) Draw the structure of 3-t-butyl-2,2-dimethylheptane.

3) Starting from the left, identify the hybridization of each carbon atom in the compound below:

sp3, sp, sp, sp3, sp2, sp2

4) Draw the Lewis dot structures of the following compounds:

a)

b)

5) Consider the rotation about the C2-C3 bond in 2-methylpentane.

a) Draw the Newman projection of the stable conformers.

>Adobe Systems

b) Draw the Newman projection of the transition states for the rotation about the C2-C3 bond.

c) Sketch the rotational energy diagram. Be sure to indicate where each of the structures you drew in parts (a) and (b) are located in this diagram. It is only necessary to depict the relative energies do not worry about the actual value of the energy of any of the conformational isomers.

6) Consider the molecule below, which is called glucose. The six member oxygen-containing ring adopts a geometry just like that of cyclohexane. There are many other possible sugar molecules that differ from glucose in the arrangements of the OH and CH2OH groups their relative cis and trans arrangements. Why do you think that glucose is the most widely found sugar in nature? Justify your answer.

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Glucose, drawn in its chair form above, has all of the substituents in the equatorial position. The equatorial position is much preferred over the axial position. If one were to swap and of the relative arrangements (cis or trans) of the OH and CH2OH groups then at least one of them would now be in the axial position and therefore is less stable. Nature likes the most stable structures, so it makes a lot of glucose.

7) Assign the formal charges to all non-hydrogen atoms this neutral molecule.