[bares1207]

molecular mass of this compound is 167 and m/z is therefore also 167. However in my spectrum there's a base peak with m/z of 137. I just can't see what group can leave that will reduce the m/z by 30. If you remove CHO that removes 29 from 169. I've tired all sorts of re-arrangements with neighboring H atoms but I just cant do it. Any ideas what the structure of this ion with m/z = 137 could be?

[Burner]

http://www.chemicalforums.com/index.php?topic=84846.0

Not sure if this helps

[bares1207]

thanks for the reply but I'm afraid not the reply on that post just said basically in short "I'm not helping you" haha

[discodermolide]

perhaps a base peak + H?

[MOTOBALL]

Facile loss of 30 amu is characteristic of the loss of NO from molecules that contain a nitro group.
BTW, were you 'tezzapot' about 3 weeks ago, with the same question?