May anybody help me to plan a synthesis of cyclopentadiene starting from cyclopentenone? I was thinking to the following:
- Reduction of cyclopentenone to cyclopentenol by enzymes
- Dehydration of cyclopentenol to cyclopentadiene by strong acid
Do you think this path may be feasible? Can anyone suggest any amelioration to it, or maybe something different (e.g. without passage through the
alcohol)?
Thank you
CarloBoffis - 14-12-2015 at 16:46
No, assuming you can reduce the ketone to an alkohol, dehydration of this will only give cyclopentene ie only one ethylenic double bound. But if you
add say bromine to this to obtain 1,2 dibromocyclopentane it may then be possible to de-hydrohalogenate this compound to cyclopentadiene but it may
also give a single acetylenic triple bound instead. I think you need to do some more reading.UC235 - 14-12-2015 at 16:54
Dehydrohalogenation of the dibromocyclopentane will definitely not give an alkyne due to ring strain. However I suspect it will mostly give
1-bromocyclopentene which will be unreactive to base.CuReUS - 15-12-2015 at 09:59