JoeFro84 - 16-4-2004 at 21:35
Hmm, not too sure how to go about this question. Today in lab, a couple of people including myself and the TA ran the Tollens test for
Cinnamaldehyde. We could not figure out why the test consistantly came up negative. No one was too sure why, as the same procedure gave a positive
test for a simpler aldehyde. Anyone have any ideas as to why the test came up negative? Could it be because cinnamaldehyde is a conjugated aldehyde?
I wasnt sure if that would make a difference. My Ochem professor wasnt even too sure on this, and I havent managed to find a good site regarding the
test and possible complications.
lordnick - 13-5-2004 at 18:48
I never bother with the Tollens test because sometimes it works and sometimes it doesn't (even with simple aldehydes in my experience).
You could try the 2,4-Dinitrophenylhyrazine test which forms a yellow precipitate with aldehydes and keytones, you could then use the chromic acid
test to see if the sample is either an aldehyde or a keytone.