[english]

Alkenes with fewer than 8 carbons cannot exist as trans stereoisomers.  My book just says it's because a ring with fewer than 8 carbons simply cannot support this configuration.

I know that, for example, cyclohexene cannot exist as a trans isomer because it would look something like this:



So my question is, if cyclohexene was disubstituted it would not exist as a trans isomer either?

-Thanks

[Dan]

I'm pretty sure that cyclo-octene can exist in the trans configuration that you posted.

As a side note, it is worth pointing out that Trans-cyclo-octene is chiral.

Try to draw or make a model of trans cyclohexene... It's really, really strained -> doesn't happen.