Madandcrazy - 4-8-2005 at 07:15
How can i get a cyclic ketone ?
I want starting with 1,3,5-cycloheptatriene
and will get 1,3,5-cycloheptatriene-7-one.
Anyone have some ideas to the syntheses ?
sparkgap - 4-8-2005 at 08:56
This might interest you:
A New, Simple Synthesis of Tropone,” Garfunkel, E.; Reingold, I. D., J. Org. Chem., 1979, 44, 3725.
(psst, "tropone" is shorter than "cycloheptatrienone" 
)
*hint*Now if someone could be kind as to search for a PDF*hint*
OK, now for my own input: compounds with seven-membered rings are not usually built from precursors with seven membered rings, so I don't think
it's a short route from cycloheptatriene to tropone. Most likely you'd have to ring-expand some appropriate six-membered precursor...
I'm feeling too weak to try to cook up a plausible synthetic pathway... sorry. 
sparky (~_~)
epck - 4-8-2005 at 09:58
Hmmm...I would be happy to post up the article if someone would be so kind to enlighten me an the correct produre for attaching a file. I have a
browse button but no add attachment or upload button.
See mood...
Edit:
Oh nevermind, I seemed to have figured it out.
[Edited on 4-8-2005 by epck]
Attachment: tropone.pdf (141kB)
This file has been downloaded 634 times
sparkgap - 4-8-2005 at 10:08
Tropylium fluoborate... yipes! I wonder if subsequent investigators have tried other tropylium salts?
epck, you might also want to look into uploading whatever you wish to attach to the "scipics" account (if there's still enough space
there ). Look for the "Sciencemadness file hosting" thread.
sparky (~_~)
praseodym - 4-8-2005 at 22:51
Hmm...Cyclic ketone. Civetone may interest you. Civetone is a cyclic ketone and one of the oldest perfume ingredients known. Its chemical name is
9-cycloheptadecen-1-one. But how do you get it, anyone?
sparkgap - 5-8-2005 at 06:12
Hunt for civets (careful, they bite and scratch!) in either North Asia or Eastern Europe. 
As to synthesis, maybe Dieckmann cyclicization or acyloin condensation of the appropriate substrates? It's a bit complicated to make large rings
actually...
sparky (^_^)
Madandcrazy - 7-8-2005 at 06:38
Hmm, is it possible get the tropone from
1,3,5-cycloheptatriene, lashing the
=O group to the -CH2- in a closed ring or open a stable -CH=CH- bonding.
look thus:
-CH2-CH=CH-
-->
-(C=O)-CH=CH-
-CH2-(C=O)-CH2-