I have 3,5,5-trimethyl-2-cyclohexene-1-one. I want to reduce the keto group to methylene. Can anybody suggest simple reducing agent/method with procedure? Thanks in advance!
Dear Vijayakumar Badathala,
Using of Sodium Borohydride-Cerium (III) Chloride. Regioselective reduction of unsaturated carbonyl groups ,2-Reduction using a 1:1 ratio of NaBH4 and CeCl3
•good route to allylic alcohols
Please, find in attach a report on: Reduction Reactions, by: Prof. Dr. Burkhard König, Institut für Organische Chemie, Uni Regensburg
It might be useful for you.
Good luck
Dear Vijayakumar Badathala,
Using of Sodium Borohydride-Cerium (III) Chloride. Regioselective reduction of unsaturated carbonyl groups ,2-Reduction using a 1:1 ratio of NaBH4 and CeCl3
•good route to allylic alcohols
Please, find in attach a report on: Reduction Reactions, by: Prof. Dr. Burkhard König, Institut für Organische Chemie, Uni Regensburg
It might be useful for you.
Good luck
Do you want to reduce the ketone to the alcohol or the methylene ?
Conversion to the tosylhydrazone and reduction with LiAlH4 (avoid migration of double bond)
Dear Prof., What about Wolff-Kishner reduction using H2NNH2, KOH, heat? Please advice.
W-K is supposed to give pyrazolines with unsaturated ketones. But with this cyclic substrate, it may be worth a shot. Tos-hydrazone also milder conditions.
Dear VK
Try borohydride exchange resin for the reduction. The reagent is mild and over oxidation may not occur,
Dear Vijayakumar Badathala,
The Wolff-Kishner reduction is an organic reaction used to convert an aldehyde or ketone to an alkane using hydrazine, base, and thermal conditions. The mechanism begins with the attack of hydrazine of the aldehyde or ketone for form an imine. Proton transfer steps then result in the formation of a N=N bond. Deprotonation of the nitrogen and a rearrangement reaction result in the formation of a carbanion and the release of nitrogen gas. The carbanion then picks up a proton from water to regenerate the base catalyst and provides the final alkane product.
There is this classic "Luche Reduction" with Sodium Borohydride and Cerium (III) chloride which will do your job.
Here is the preparation of your desired compound:
http://pubs.acs.org/doi/abs/10.1021/ja01078a023
You can also try the reduction of the ketone with LiAlH4:
http://www.nrcresearchpress.com/doi/pdfplus/10.1139/v77-142
(Luche method can be too weak for such a hindered ketone), then convert the alcohol into the mesylate and reduce it with LiBHEt3 (J. Am. Chem. Soc. 1990, 112, 5290-5313) or NaBH4-NiCl2-MeOH (chemistry-chemists.com/chemister/Mechanizms/reductions.pdf), or LiAlH4 in ether.
Reduction of the isophorone tosylhydrazone will give another regioisomer or a mixture: http://pubs.acs.org/doi/abs/10.1021/jo00319a038?journalCode=joceah
Can use NaBH4 CeCl3 in 1:1 ratio as suggested by prof .Talaat I .E I-EMary
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