Allylic Amidation of Olefins by Ene Reaction of Acylnitroso Compounds Generated in situ by Oxidation of Hydroxamic Acids

Abstract

A one‐pot allylic amidation procedure, which employs the ene reaction of acylnitroso compounds 2 with electron‐rich olefins 3a,b, is presented; the acylnitroso enophile is generated in situ by oxidation of hydroxamic acids 1 with iodosobenzene diacetate. The resulting N‐allylhydroxamic acids 4 (ene products) are quantitatively acetylated for ease of handling; as an example, the reduction of the acetylated derivative 5b by samarium diiodide was carried out to afford the N‐allyl amide 6b in quantitative yields.

Organic Dye‐Photocatalyzed Acylnitroso Ene Reaction

“…The products obtained provide access to α,β‐disubstituted amino acids, which have few direct synthetic methodologies 14. Poor yields were reported previously by using tiglic acid derivatives as the ene substrates because of the electron‐deficient double bonds 6. Moderate‐to‐good yields were obtained with tiglic acid, tiglic esters, and tiglic amide as the alkene partners under our reaction conditions (Table 3, entries 5–8).…”

Peroxidase-induced C–N bond formation via nitroso ene and Diels–Alder reactions

“…In our sustainability assessment, we will compare the herein presented and optimized benchmark reaction for the synthesis of 2a with state-of-the-art methodologies utilizing traditional stochiometric oxidants as well as metal-mediated catalytic processes. The former utilizes diacetoxyiodobenzene as oxidant in a solvent mixture of dichloromethane and DMF, 8 the latter systems consist of either iron( iii ) chloride as catalysts with hydrogen peroxide as oxidant (in isopropanol at 100 °C), 13 or copper( i ) chloride as catalyst with air as oxidant (in THF at r.t.). 12 In addition to a qualitative assessment of individual reaction components, also a comparative analysis of E -factors was considered useful to identify sustainability advantages but also reveal development targets for potential process-related optimizations.…”

Development of a Concise Synthesis of (−)‐Oseltamivir (Tamiflu)

“…Initially, ene reaction was examined. It is known that an ene type reaction between an alkene and a nitroso compound affords an allylic amine 16. It is proposed that the reaction occurs via a six-membered transition state (Scheme 7).…”