When drawing a wedge-dash structure, we imagine that we are looking at a molecule side-on. For example, consider how the molecular models of ethane, propane, and butane, below, match up with their respective wedge-dash structures.
Tutorial: Drawing wedge-dash structures
Exercise: Draw 1-fluoropropane as a wedge-dash structure in the given conformation.
Note: The fluorine atom is represented in light-green.
Click on the tabs for hints.
Imagine looking at the model side-on.
Connect the atoms in the plane of the page with straight lines.
Note: The carbon atoms have been highlighted in blue.
Label the non-carbon atoms, ie: the two terminal hydrogen atoms.
Add wedges for all atoms coming out of the page.
Add dashes for all atoms going into the page and put appropriate labels (H and F).
Sometimes it is helpful to keep track of bond rotations by looking at a C-C bond from a 45° angle or head-on, rather than side-on. We can do this by using two new molecular representations: sawhorse projections and Newman projections.