Us SnCl2

 There are dozens of ways to do this. I would use hydrogenation with Pd/C with hydrogen or formate as first choice. You can use SnCl2/HCl, but it's not very green. As alternative you  can  use iron powder or zinc with HCl, sodium dithionate and many more. There a long discussion of the pro's and con's of different nitro reduction reagents on Researchgate in the link

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/14

 Thanks a lot :-) :-)

0.1 mole of R-NO2 was added  to mixture 0.2 mol of SnCl2 in 350 ml of concentrated HCl and stirred at 70 ° - 90 ° C for 30 minutes (chromatographic control). It can be possible at lower temperatures, depending on the compound.

In some cases I reduced NO2 group with hydrazine hydrate  and Raney Ni

H2 at atmospheric pressure (no special apparatus needed), with Pt/C in acetic acid. 

No workup: just filter and evaporate.

 I was successful in reducing aromatic nitro groups to NH2 using Fe, MeOH, AcOH and water under sonication, 30°C and open air. The reaction takes about 2 to 3 hrs with quantitative yields but the workup is bit demanding. Dear you can check this paper for the molar ratios to be used.

http://www.tandfonline.com/doi/full/10.1080/00397910701481195?src=recsys

Please try iron hydrochloride method if your entity consist of multi-substituents, in that case Sn or SnCl2 is insufficient, and usually yields multi products.

Instead of non-metals/Transition metal, try as follows:

1. Sodium dithionite-5.0eq

2. Potassium carbonate-0.6eq

3. water-3.0 Vol with respect to RM

4. 1,4-dioxane-7.0 Vol with respect to RM

SnCl2

SnCi2 in the presence of HCl solution.

SnCl2/HCl

I used SnCl2

I used this methodology Fe powder (5eq), Ethanol: Water/4:1, Con HCl (1V) @ 90°C.

I have successfully used LiAlH4 / THF to reduce NO2 together with an olifinic double bond in the same compound

Recently I tried reduction of NO2 in Etahnol using Fe (5 eq) and Ammonium Chloride (10 eq) with 2 ml water at reflux temp. Filter hot. Removal of EtOH will give you the product.

SnCl2.Don't have idea about the molar ratio though

Try what you have available, and choose the best yielding, or more convenient. In my lab, Clemmensen usually works clean, but not great on the yield side. SnCl2 did very good when dealing with dinitro compounds.

Catalytic hydrogenation can also be used, and usually works great, best yield of all methods, and cleanest.

I think Pushkal Samadhiya gave a good answer. Try it and I think it will work

for me the good ratio is to use 4-5 excess of SnCl2.2H2O

try hydrate hydrazine

I would recommend Hydrogenation with Pd as a catalyst as a first choice

SnCl2-9H20 worked too but the workup is tricky: you can dilute your mixture with acqueous bicarbonate and then extract to EtOAc. Otherwise filtering the mixture on Celite, evaporiting the solvent and recrystallize the product is an option

Fe powder in HCl 37% gave me the desired compound but with low yield

As other said sodium dithionite or sodium sulfide are other good options especially in the case you have acid-sensitive or hydrogen-sendiyive starting materials

Good luck!

SnCl2 and EtOAc as a solvent at 50°C worked fine for me.

Be aware that the work-up may be challenging. You have two choices: either dilute your mixture with plenty of H2O and then extract to EtOAc or filtering the mixture on celite and then performing the extraction H20/EtOAc

Regards

Can use SnCl2 with 2 mol of water

Regards

i want to reduce Aromatic NO2 to NH2 without changing any other functional group like ketone ...how can i ? now i am having SnCl2 LiAlH4 NaBH4 Fe

use excess of tin chloride dihydrate. at least 6 equivalents to your substrate and heat it at 70 degree centigrade in HCl (37 %) for 1-2 hr under inert atmosphere.

The best reducing agent to convert NO2 group to NH2 group is SnCl2 . However, you need con. HCl during reduction under reflux condition.

Dithionite and sulphide both work, if you can stand the stench.

Otherwise ANY active metal, Sn works, Zn, Fe, I have used. All have different "tricks" you must find, and affect the yields.

In my book, stannous chloride is one of my first choices.

Also, excess Ni Raney in refluxing ethanol (no need of extra H2), or catalytic hydrogenation can reduce NO2 groups too.

Sn or Sn compound give a messy work-up. i recommend Marcelo Preite 's answer. Zn/acetic acid or Fe/Acetic acid work great.

Hydrazine hydrate with Pd/C in EtOH is quite efficient and the work-up is very easy. Use a glass microfiber filter instead of Celite to withdraw the catalyst.

I used also SnCl2/HCl for the reduction of nitrobenzene to aniline