[Elnaz]

Hi there,

I need to know what is the smallest cyclic diyne?

thanks

[curiouscat]

This?



Or

[Elnaz]

thanks curiosecat, could you write the source please?

[Arkcon]

I don't believe there's likely to be a source dedicated to just this question.  I would have suggested you try ever smaller diyne and see if they exist.  Its not likely a cyclic diyne exits if the complementary cyclic diene doesn't exist, and there's ring strain even on smaller cyclic alkanes.  Unless you're looking for theoretical predictions based on bond lengths and hybridizations, but that's a pretty advanced topic.  I'm also guessing, since you need a source or citation, you'd not be satisfied with buying a molecular modeling kit and seeing how small of one you can make without the model popping apart.

[curiouscat]

I don't believe there's likely to be a source dedicated to just this question.  I would have suggested you try ever smaller diyne and see if they exist.  Its not likely a cyclic diyne exits if the complementary cyclic diene doesn't exist, and there's ring strain even on smaller cyclic alkanes.  Unless you're looking for theoretical predictions based on bond lengths and hybridizations, but that's a pretty advanced topic.  I'm also guessing, since you need a source or citation, you'd not be satisfied with buying a molecular modeling kit and seeing how small of one you can make without the model popping apart.

One relatively cheap option might be to use something like Gaussian to calculate relative stabilities. Though not sure how you'd use that to say if or not they exist.

[AWK]

http://onlinelibrary.wiley.com/doi/10.1002/hlca.19750580121/abstract

1,3-cyclooctadiyne cannot exist.