Synlett 2006(1): 0153-0154  
DOI: 10.1055/s-2005-922781
SPOTLIGHT
© Georg Thieme Verlag Stuttgart · New York

Sodium Nitrite (NaNO2)

Dan Bernardi*
Faculté des Sciences, Université Paul Verlaine-Metz, 1 Bld Arago, 57078 Metz Cedex 3, France
e-Mail: dan.bernardi@umail.univ-metz.fr;

Further Information

Publication History

Publication Date:
16 December 2005 (online)

Biographical Sketches

Dan Bernardi was born in 1977 in Metz (France). He studied ­Chemistry at the Paul Verlaine University of Metz (1998-2005) where he is currently carrying out his PhD under the supervision of Prof. Amadou Dicko. His area of interest in the research group of Prof. G. Kirsch is the development of new analogues of glutathione as probes in the study of apoptosis.

Introduction

The well-known NaNO2 (mp 271 °C, d = 2.17) has ­multiple applications in organic synthesis but also in ­medicine as a vasodilator, bronchodilator and antidote against cyanide and H2S poisoning. It is produced in the human body from saliva and sodium nitrate to control bacteria in the stomach.

The synthetic utilities of NaNO2 have been extensively investigated in organic chemistry. Nitrosation of primary amines with nitrous acid (generated in situ from sodium nitrite and a strong acid) leads to diazonium salts. These salts are useful synthetic intermediates used in named ­reactions like Sandmeyer, Balz-Schiemann, [1] Pschorr, [2] and Heck [3] or in the manufacture of diazo dyes. [4] NaNO2 is also used in the synthesis of alkyl nitrites, [5] reagents used for the synthesis of diazonium salts in non-aqueous media [6] or for the diazotization of primary aliphatic amines [7] in DMF.

NaNO2 reacts with SO2 and potassium hydrogen carbonate to afford potassium hydroxylaminedisulfonate salt, which gives after oxidation nitrosodisulfonic acid di­potassium salt. This Fremy’s salt is a useful reagent for the selective oxidation of phenols and aromatic amines to quinones (the Teuber reaction). [8]

Hydroxylamine hydrochloride is synthesized from NaNO2 in a three-step procedure. [9]

Abstracts

(A) tert-Butylcarbazate reacts with NaNO2 in an aqueous media to afford tert-butyl azidoformate [10] which is a convenient reagent for the acylation of amine, hydrazine and similar compounds. [11]

(B) N-Nitroso derivatives [12] of secondary amines are prepared by the action of NaNO2 in aqueous acetic acid. The latter can be reduced by LiAlH4 to give the corresponding hydrazine derivatives.

(C) Oximes [13] can also be easily obtained from malonates or ­malononitrile and NaNO2 under very mild conditions. Reduction of the oxime allows the formation of the amino derivative.

(D) The benzotriazole ring system [14] is built from monoacyl-o-­phenylene diamine and NaNO2 in aqueous acetic acid.

(E) NaNO2 is a very useful reagent for the production of simple ­aliphatic nitro compounds. [15] An example from α,β-enones is shown here.

(F) Lindén et al. [16] have used NaNO2 in the formation of a tricyclic alloxazines. Nitrite was the key reagent for this ring-closure step.

(G) Liu et al. [17] have shown the utility of NaNO2 as a cocatalyst for the oxidation by TEMPO of alcohols to ketones in water.

(H) Abidi [18] converted the isopropylidene group in geraniol chain into an alkyne group by the action of an excess of NaNO2 in acetic acid.

(I) Panzella et al. [19] showed that NaNO2 in acetate buffer (0.05) M mediated the decarboxylative conjugation of caffeic acid with ­glutathione under mildly acidic conditions.