Antimorph - 8-7-2017 at 05:45
Hello everybody,
First off I'm new to sciencemadness and hope I'll have some good discussions here since organic chemistry is my passion since many years.
Now to the actual topic. I tried many different reduction methods of Nitroaldol products ranging from NaBH4/CuSO4 to Zinc/Potassium formate or
Gallium/Aluminium alloy or Raney Nickel with hydrazinium monoformate. Some of them worked well others not so well depending on the substrate of
course.
I now wanted to try a different method where only an aliphatic Nitro group needs to be reduced which is easily done.
I added my reaction sketch aswell so that you have a better overview. It involves the tosylation of Indole-3-carbinole with subsequent nucleophilic
substitution with a Nitronate.
To the questions:
Has anybody any knowledge about the stability of the Tosylate? Is it possible to isolate it without problems?
The other question is, is it possible to completely turn the Nitroalkane to the corresponding Nitronate salt? In homology you can think of a Ketone or
Aldehyde and its corresponding Enolate which can be produced with a non nucleophilic base like Sodium hydride. I am aware that Sodium Nitronates are
potential primary explosives and that they need to be handled with absolute care and dryness. I know aswell that I could use less dangerous bases like
Triethylamine but the idea is to fully transform the Nitroalkane to the Nitronate and keep it in solution, so that I can use a dropping funnel to drop
the Nitronate to the Tosylate while the reaction is properly cooled with an ice bath.
Some papers:
S. Shankare, D. C. Shankare, Dep. Stud. Chem., Tetrahedron 58 (2002) 2211-2213
M. Periasamy, M. Thirumalaikumar, J. Organom. Chem. 609 (2000) 137–151
John Wiley & Sons, Inc "NITRILE OXIDES, NITRONES, AND NITRONATES IN ORGANIC SYNTHESIS - Novel Strategies in Synthesis Second Edition"
P. K. Pradhan, S. Dey, P. Jaisankar, V. S. Giri, Dep. Med. Chem.
ISSN 0039-7911 print/1532-2432 online DOI: 10.I081/SCC-200051681
C. Gowda, B. Mahesh, S. GowdaInd. J. Chem. 408, January 2001 75-77
