Practical Azidation of 1,3‐Dicarbonyls

Abstract

An operationally simple, direct azidation of 1,3-dicarbonyl compounds has been developed. The reaction proceeds readily under ambient conditions using sodium azide and an iodine-based oxidant such as I(2) or 2-iodoxybenzoic acid (IBX)-SO(3)K/NaI. In particular, the latter method, as a new and well-balanced oxidizing agent, shows excellent functional group tolerance and substrate scope and thus allows access to a variety of tertiary 2-azido and 2,2-bisazido 1,3-dicarbonyl compounds that would be more difficult to access by using traditional methods. Because the azide-containing products easily undergo 1,3-dipolar cycloaddition with alkynes, our report represents a novel route to analogues of sensitive complex molecules.

IBX‐Mediated Dehydrogenation of Substituted β‐Oxonitriles

“…Under these conditions, unsaturated product 2a was obtained in 95 % yield; according to NOESY contacts, only the E ‐configured diastereoisomer was formed. A similar yield was achieved in the presence of the less reactive IBX‐SO 3 K, an oxidizing agent that we introduced in 2012 as a chemoselective alternative to IBX 4e. However, the reaction with IBX‐SO 3 K required a markedly longer reaction time to reach full conversion of the starting material.…”

Metal‐Free Oxidative Carbon‐Heteroatom Bond Formation Through C–H Bond Functionalization

“…Kirsch and co‐workers have very recently developed a procedure for operationally simple, direct azidation of 1,3‐dicarbonyl compounds under ambient condition by use of sodium azide and iodine‐based oxidants such as molecular iodine or an IBX‐SO 3 K/NaI combination 46. The latter method showed excellent functional group tolerance and substrate scope (Scheme ).…”

An Efficient Tertiary Azidation of 1,3‐Dicarbonyl Compounds in Water Catalyzed by Tetrabutylammonium Iodide

“…[8] Gade and Waser reported azidation of β-keto esters and silyl enol ethers with a benziodoxole reagent and a Lewis acid (Scheme 1).…”