Sciencemadness Discussion Board

PhCH2NO2 from PhCH2OH

whupharm_xu - 11-9-2006 at 00:38

we take the following procedure in preparing PhCH2NO2 from PhCH2OH.
To a solution of benzyl alcohol in CH2Cl2 was added NaNO2. To this mixture was added HOAc and left at r.t. for 5 minutes.Then concd HCl was aded to this mixture and left without stirring for about 14 h. Two points was found in TLC plate with Rf 0.9 and 0.6, and the corresponding products were PhCH2ONO and PhCHO respectively.The procedure was taken entirely according to a paper in SYNLETT(2000,7,1064),but in fact the aim product was not obtained.
now we don't know what happened in our experiment, anybody can give me some suggestions?

solo - 11-9-2006 at 02:42

Reference Information

Note:deleted due to it's being flawed and untrue..............so save your chems for a better formula..........

A Simple and Highly Efficient Procedure for the Preparation of Aliphatic Nitro Compounds Directly from Alcohols
Baruah, Apurba; Kalita, Biswajit; Barua, Nabin C.
SYNLETT(2000,7,1064)


Abstract:
A series of enantioenriched 4-hydroxy-1-alkenyl carbamates
was prepared by (-)-sparteine-mediated homoaldolization.
These were transformed into unsaturated oxacycles, involving simple
synthetic transformations, with ring-closing metathesis (RCM)
as the key step.

[Edited on 11-9-2006 by solo]

[Edited on 11-9-2006 by solo]

Vitus_Verdegast - 11-9-2006 at 08:04

Quote:

To a solution of benzyl alcohol in CH2Cl2 was added NaNO2


You will only obtain benzyl nitrite using this procedure. Using DMF instead should give you a mixture of benzyl nitrite and alpha-nitrotoluene.

Kornblum, New Synthesis of Aliphatic Nitro Compounds J. Amer. Chem. Soc. 78, 1497 (1956)
http://www.erowid.org/archive/rhodium/chemistry/nitroalkane....

Nicodem - 11-9-2006 at 09:29

That Synlett paper was debunked as bullshit by some other authors some time later. Search in the next volumes of the journal, it is there somewhere. I can't even believe such an obvious hoax paper ever went trough the peer review system.
It is known for more than a century that alcohols, NaNO2 and HCl gives alkyl nitrites, so it is beyond my imagination what kind of idiotic peer review could given a green light to such a paper.

whupharm_xu - 11-9-2006 at 18:38

thank you for all!
Now my first thing is to find an easy and efficient method in preparing PhCH2NO2 using PhCH2OH. the procedure of the jacs paper(1956) is not promising for preparing PhCH2NO2, the low yield and high cost (using PhCH2Br and DMF) were its great disadvantages.

tr41414 - 16-9-2006 at 14:42

I belive that PhCH2OH + HCl > PhCH2Cl + H2O, PhCH2Cl + NaNO2 > PhCH2NO2 + PhCH2ONO (byproduct) + NaCl will work, if done as two separate reactions... The references for both reactions can be found in Rhodium archive...

http://designer-drugs.com/pte/12.162.180.114/dcd/chemistry/b...

http://designer-drugs.com/pte/12.162.180.114/dcd/chemistry/n...
Not really the case of benzylchloride, but should be similiar...