Chapter 4 Vocabulary

Steric interactions that occur between axial substituents in a chair conformation.

A hydrocarbon that lacks π bonds.

A substituent lack- ing π bonds and comprised of only carbon and hydrogen atoms.

The increase in energy associated with a bond angle that has deviated from the preferred angle of 109.5°

A conformation in which the dihedral angle between two groups is 180°.

For chair conforma- tions of substituted cyclohexanes, a position that is parallel to a vertical axis passing through the center of the ring.

A structure containing two rings that are fused together.

A conforma- tion of cyclohexane in which all bond angles are fairly close to 109.5° and many hydrogen atoms are eclipsing each other.

In a bicyclic system, the carbon atoms where the rings are fused together.

The lowest energy conformation for cyclohexane, in which all bond angles are fairly close to 109.5° and all hydrogen atoms are staggered.

A three-dimensional shape that can be adopted by a compound as a result of rotation about single bonds.

An alkane whose structure contains a ring.

C6H12. A colourless flammable liquid cycloalkane obtained from petroleum or by hydrogenating benzene, and used as a solvent and paint remover.

Having the same energy.

The angle by which two groups are separated in a Newman projection.

A conformation in which groups are eclipsing each other in a Newman projection.

For chair conformations of substituted cyclohexanes, a position that is approximately along the equator of the ring.

For cyclohexane, the steric interactions that occur between the flagpole hydrogen atoms in a boat conformation.

A conformation that exhibits a gauche interaction.

The steric inter- action that results when two groups in a Newman projection are separated by a dihedral angle of 60°.

The heat given off during a reaction in which an alkane reacts with oxygen to produce CO2 and water.

The International Union of Pure and Applied Chemistry. An organization that sets the rules for nomenclature (naming compounds).

In nomenclature, a number used to identify the location of a substituent.

A drawing style that is designed to show the conformation of a molecule.