Cycloalkanes and Their Conformations

These flashcards cover key concepts, definitions, and types of strain related to cycloalkanes and their conformations.

Cycloalkanes

Saturated cyclic hydrocarbons with the general formula CnH2n.

Cis-Trans Isomerism

Isomerism occurring when substituents in a cyclic compound can occupy the same side (cis) or opposite sides (trans).

Angle Strain

Strain in a molecule when bond angles deviate from the ideal tetrahedral angle of 109°.

Torsional Strain

Strain due to eclipsing interactions between neighboring atoms, leading to increased energy.

Steric Strain

Strain arising from repulsive interactions when atoms are too close to each other.

Chair Conformation

The preferred, strain-free three-dimensional shape of cyclohexane.

Axial Position

A position on a cyclohexane ring where substituents are oriented up or down, parallel to the ring axis.

Equatorial Position

A position on a cyclohexane ring where substituents are oriented in the plane of the ring, around its equator.

1,3-Diaxial Interaction

Steric strain that occurs from axial substituents on a cyclohexane ring interacting with axial hydrogens on carbons three positions away.

Ring-Flip

A conformational change in cyclohexane that interconverts axial and equatorial positions.

Trans-Decelean

Cis–trans stereoisomer where substituents on the bridgehead carbons are on opposite sides.

Polycyclic Molecules

Molecules containing two or more interlinked cycloalkane rings.

Decalin

A polycyclic compound consisting of two cyclohexane rings fused together.

Prostaglandins

Cyclic compounds that act as potent hormones controlling various physiological processes.

Cyclopropane Strain Energy

The measure of energy required to overcome the angle strain and torsional strain in cyclopropane.

Cis-Trans Isomers vs Constitutional Isomers

Cis-Trans isomers have the same connectivity but differ in spatial arrangement, while constitutional isomers differ in connectivity.

Stereochemical Isomers

Compounds with the same molecular formula and connectivity but different spatial arrangements.