Using what you know about the conformational energetics of substituted cyclohexanes, predict which of the two decalin isomers is more stable. Explain your reasoning.

Convert each Newman projection to the equivalent line–angle formula, and assign the IUPAC name.

(a)

(b)

Convert each Newman projection to the equivalent line–angle formula, and assign the IUPAC name.

(c)

(d)

Convert each Newman projection to the equivalent line–angle formula, and assign the IUPAC name. g.

(g)

(h)

Draw Newman projections along the C3―C4 bond to show the most stable and least stable conformations of 3-ethyl-2,4,4-trimethylheptane.

Conformational studies on ethane-1,2-diol (HOCH₂–CH₂OH) have shown the most stable conformation about the ­central C―C bond to be the gauche conformation, which is 9.6 kJ/mol (2.3 kcal/mol) more stable than the anti conformation. Draw Newman projections of these conformers, and explain this curious result.

The most stable form of the common sugar glucose contains a six-membered ring in the chair conformation with all the substituents equatorial. Draw this most stable conformation of glucose.

This is a Newman projection of a substituted cyclohexane. a. Draw the equivalent chair form.

This is a Newman projection of a substituted cyclohexane.

b. Draw the equivalent structure using wedge and dash notation on a cyclohexane hexagon.

This is a Newman projection of a substituted cyclohexane.

c. Give the IUPAC name.