If anyone knows some other interesting methods, I'd like to know. How do you do reduction of aromatic nitro or nitroimidazole ? I'm not sure why but the borohydride doesn't seem to work all the way to the alkane, it stops at the double bond for which it has an affinity (refer my comment). There has to be something as additional reagent altering the reducing properties of NaBH4 to enable it to reduce the nitro group to the amine, it can't do this by itself. I started on a mechanism before remembering about, you know, books. Is whatever I see on the internet temporarily present in the RAM? Why does CDCl3 give a triplet in NMR spectrum and why does it have equal intensity? Determining amount of Catalyst using Mol %, I am currently attempting to replicate a reaction directly from a protocol. Dissolve first Ar-Nitro in HCl and at 0 degree celsius portion-wise addition of Zn powder. Selective reduction of aromatic nitro compounds with stannous chloride in non acidic and non aqueous medium. I am having trouble understanding how much catalyst to use because the authors do not state if the mol% is in reference to which of the reactants or both. I read that it could be HOD peak, but does HOD peak usually appear that high? Which one is the best procedure for the reduction of aromatic nitro compounds? I've just made some formic acid from oxalic acid, and will split the yield into 2. As for the copper catalysts I'm only now reading about that it seems very interesting. Press J to jump to the feed. Addition of NaBH4 slowly does not form 282 the black Co2B (H) precipitate, but does reduce the nitro compound. Neither $\ce{LiAlH_4}$ nor $\ce{NaBH4}$ are able to reduce an isolated $\ce{C=C}$ bond. 19-41 (p.1553) "Most metal hydrides, including NaBH4 and BH3, do not reduce nitro groups at all, though both aliphatic and aromatic nitro compounds have been reduced to amines with NaBH4 and various catalysts, such as NiCl2 or CoCl2.". The conversion can be effected by many reagents. If you use any metal that can adsorb the hydride on the surface. Reaction was not moving forward. But I'm intrigued that borohydride with CuSO4 could be used. Satoh, T., Mitsuo, N., Nishiki, M., Inoue, Y., and Ooi, Y. That is what the Cu(II) salt is for in the respective method using this. Press question mark to learn the rest of the keyboard shortcuts, https://www.thevespiary.org/rhodium/Rhodium/chemistry/nitrostyrene.nabh4.html, https://chemistry.mdma.ch/hiveboard/novel/000426052.html, https://chemistry.mdma.ch/hiveboard/rhodium/nitro2amine.zn-formate.html, http://www.sciencemadness.org/talk/viewthread.php?tid=4965. I should have added this info to my post, sorry :). New comments cannot be posted and votes cannot be cast. Sodium sulfide can be a useful altenative for substrates where hydrogenation or acidic conditions are not compatible. There are four hydrogens ("tetrahydido") around the aluminium in a negative ion (shown by the "ate" ending). How to ingest and analyze benchmark results posted at MSE? Not sure about that specific compound but SnCl2 + NaBH4 seems to preferentially reduce aryl-nitro groups and leave other groups alone. https://www.researchgate.net/post/What_are_the_best_reagents_to_reduce_aromatic_nitro_to_amine_Does_anyone_have_suggestions_other_than_Raney_Ni_Pd_C_Sn_HCl_Fe_HCl, http://ro.uow.edu.au/cgi/viewcontent.cgi?article=1174&context=scipapers. How can an aromatic ketone be reduced in the presence of a nitro group? We do not condone breaking any laws in your area, but are more than happy for you to share your dreams with us. It would makes sense because NaBH4 has an affinity for α,β-unsaturated compounds such as enols because it's soft nucleophile, and a α,β-unsaturated nitro is basically a superpowered enol cause of the electonegative induction of the nitro. My planet has a long period orbit. The carbonyl is protonated and the first hydride delivery gives the alcohol. You might be able to do without the copper. I have used Zn and %2 HCl but the amount of the substance is poorly. Cu gets reduced to Cu(I), right? Use the BACK button on your browser to return to this page. rev 2020.11.24.38066, Sorry, we no longer support Internet Explorer, The best answers are voted up and rise to the top, Chemistry Stack Exchange works best with JavaScript enabled, Start here for a quick overview of the site, Detailed answers to any questions you might have, Discuss the workings and policies of this site, Learn more about Stack Overflow the company, Learn more about hiring developers or posting ads with us. Best method of aromatic nitro to aromatic amine. How to consider rude(?) I need a convenient procedure for the reduction nitro group of aromatic compounds! 3) … This is a subreddit for all the lost Bees. Chem. Be careful, fresh quality of Na2S.9H2O is important. Reflux/heated up depends upon the functional group. Catalyzed borohydride reductions are presented by the functional groups which are reduced. Na2S can sometimes selectively reduce one nitro group in the presence of other nitro groups. I started on a mechanism before remembering about, you know, books. The protocol states that they use 2 mmol of reactant 1, and 0.5 mmol of reactant 2 and then 20 mol% of catalyst. Stack Exchange network consists of 176 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. Most papers are using Sn/tin powder with the present of ethanol and HCl. of Zn is needed can be more or less depending on how slowly you add Zn. LiAlH4 can reduce carboxylic acids, epoxides, lactones, nitro groups, nitriles, azides, amides, acid chlorides and esters to primary alochols; NaBH4 does not b. NaBH4 rapidly reduces aldehydes and ketones, slowly reduces esters 3) Does not violently react … 25, 839–842. Jpn., 1974, 47, 2323-2324) has shown that the tosylhydrazone of cyclohexanone can be reduced to cyclohexane with $\ce{NaBH4}$ in polar aprotic solvents. With 5 to 10 bar hydrogen pressure. You will most likely be successful if you convert the ketone to the corresponding tosylhydrazone and reduce that with $\ce{NaCNBH3}$ ().A previous study (Bull. It only takes a minute to sign up. Soc. I've been stuck on this reduction for a while now. Would be greatly appreciated.d. Which groups can’t be reduced? Join ResearchGate to find the people and research you need to help your work. 2) How come H2/Nickel reduces C=C bond but LiAlH4 doesnt? Northwestern University Not sure about that specific compound but SnCl2 + NaBH4 seems to preferentially reduce aryl-nitro groups and leave other groups alone. In a multiwire branch circuit, can the two hots be connected to the same phase? You reduce the nitroalkene to nitroalkane which then can be reduced by a zinc / formate solution or some other method.