The Nitro to Carbonyl Conversion (Nef Reaction): New Perspectives for a Classical Transformation

Abstract

This review article reports new procedures and practical application of the nitro to carbonyl conversion that appeared in the literature after our\ud comprehensive report published in 2004. Beside traditional and well explored reactant systems, new procedures including the utilization of molecular oxygen and photoredox catalysis have been introduced for the Nef reaction. Of notable interest is the utilizationof the nitro to carbonyl conversion in tandem and cascade processes aimed at the preparation of hetero and carbocyclic derivatives

Total Synthesis of Mesembrine – The Construction of Quaternary Stereocenters by Gold‐Catalyzed Diyne Desymmetrization

“…In the first total synthesis of racemic mesembrine by Shamma and Rodriguez the quaternary stereocenter is formed by an allylation reaction of 2‐aryl‐cyclohexanone 3 (Scheme ) . This ketone was formed by a Diels‐Alder reaction of nitroalkene 2 with butadiene and subsequent Nef‐reaction. The terminal alkene in the allylation product 4 is then oxidatively cleaved to the carboxylic acid followed by a reduction of the corresponding carboxamide.…”

Sulfonyl Azoles in the Synthesis of 3-Functionalized Azole Derivatives

“…Their reaction with nitromethane under basic conditions affords N ‐protected nitramine 12 via the corresponding N ‐acylimine 11 . A subsequent oxidative Nef reaction with KMnO 4 finally provides the α‐amino acids 13 24…”

Applications of Sodium Nitrite in Organic Synthesis

“…Additionally the use of NaNO 2 in Nef reaction and Abidi transformation is also cited. The Nef reaction which was reviewed by Ballini and Petrini, include transforming secondary nitro‐derivative into keto‐derivative and primary nitro‐derivative into acid in the presence of NaNO 2 and AcOH (Scheme ). The Abidi transformation relates to reaction of NaNO 2 with isopropylidene group to afford alkyne via formation of a cyclic intermediate as shown in Scheme and its development was comprehensively reviewed by Zard …”