# How should a triple bond be depicted in skeletal structures?

Draw the skeletal structure for the following compound: $$\ce{HOCH2CH2OCH2C#CCH2CH(CH3)2}$$

I can't figure this out.

I can draw it up until the triple bond. My professor marked off because the triple bond was not drawn correctly.

So, is the triple bond depicted any differently from the other bonds in the molecule? If so, why?

My guess, is that you forgot to take the linear disposition of the carbon-carbon triple bonds into consideration.

So the bond lines cutting through four carbon atoms will be linear, and not zig-zagged as in the rest of the molecule (the latter implies tetrahedral geometry accorded by the $$sp^3$$ carbon-carbon bonds)

The first diagram may feel more "graceful" (the term I used when I defended my incorrect depiction of the triple bond to my teacher when he asked me a similar question a while back), but it is incorrect.

A triple bond involving carbon should be drawn linearly. In general, if there are multiple consecutive atoms in a molecule which have a linear geometry, they should be drawn linearly. This is the case for the C–C≡C–C unit in an alkyne.

Atoms that are isoelectronic with carbon and bearing two double bonds (or one single bond and one triple bond) should be drawn with the bonds separated by a 180° angle.

This includes carbon itself, of course. Some examples are given, including:

Note the 180° angles at the nitrile carbon (on the left), as well as both the carbon and nitrogen (on the right). Furthermore:

Large rings that contain triple bonds should depict the triple bonds in a linear fashion, just as they would be depicted in an acyclic diagram.