What would the IUPAC name of the molecule:

H2C=C=CH2 be?

is 1,2-propene right?

3 answers

It has two double bonds and should be named a diene. I would name it 1,2-propadiene. But note that the double bonds can't be arranged any other way; therefore, I don't know if the 1,2 is necessary or not. Propadiene may be sufficient but I'm not up enough on IUPAC rules for organic nomenclature to know.
Here's a link but that doesn't prove anything unless it specifically says it's IUPAC approved. I have a call in to a friend of mine who is an organic chemist but I've not heard from him.
http://en.wikipedia.org/wiki/Propadiene
http://en.wikipedia.org/wiki/Propadiene
My friend called and said he thinks propadiene is sufficient.
Thanks!