Conformation Section

[rapodaca]

Describe what conformation means and how it's used. It will be helpful to develop a visual notation system, but it's not clear what it should be.

• conformation
  • restricted rotation about a bond
  • limited to double bonds
• partial parity bonds (PPB)
  • values: Up; Down
  • must be adjacent to a double bond
  • must be paired on opposite sides of double bond
• interpretation
  1. view double bond from top of double bond plane
  2. for each neighbor bond, decide position (Up/Down within plane) relative to its double bond terminal
  3. invert parity if bond viewed in direction of high-to-low atom index
• defined by at least two PPB's on opposite double bond terminals
• examples
  • trans-butene
  • others...
• error states
  • there are many possible, and they must be reported
  • "up" "up", "down" "down"
  • only setting one side
  • propene
  • exception: adjacent to another PPB system
• unrepresentable
  • cyclooctatetraene