Hydroxyamination of Olefins Using Br-N-(CO₂Me)₂

Abstract

The hydroxyamination reagent Br-N-(CO2Me)2 underwent Markovnikov addition to various olefins in the presence of catalytic BF3·OEt2 and provides efficient access to aminoalcohols. The reaction provided the trans-1-bromo, 2-N-bis-carbamate adduct stereoisomer in all cases. The resulting adduct underwent cyclization to give an oxazolidinone, which could be readily hydrolyzed to an oxazolidin-2-one or an amino alcohol.

Copper-catalyzed intermolecular oxyamination of olefins using carboxylic acids and O-benzoylhydroxylamines

“…With the importance of 1,2-oxyamino motifs as privileged pharmacophores, the development of facile and efficient access to this class of molecules is highly valued. Toward this end, intermolecular olefin oxyamination allows for direct and modular installation of both oxygen and amino groups to readily available olefins in a single step, representing a powerful and appealing approach over multistep sequences [ 7 – 9 ]. Sharpless reported the first examples of this strategy using osmium tetroxide and amines to generate imido osmium intermediates ( Scheme 1 ) [ 10 – 12 ].…”

An Interrupted Pummerer/Nickel‐Catalysed Cross‐Coupling Sequence

“…Stilbenes are typically synthesised through Mizoroki–Heck coupling reactions using palladium catalysts, and the few nickel‐catalysed processes require elevated temperatures or specialised catalysts . Alternatively, substituted stilbenes can be accessed via styrenyl halides, but these can be hard to access and unstable.…”

Alkene Syn- and Anti-Oxyamination with Malonoyl Peroxides

“…Subsequent reaction of 61 (R 1 = CO 2 Me) under acidic conditions gives 62 , which can undergo a 5- exo - tet cyclization, inverting the relative stereochemistry of the oxygen substituent and leading to 63 . Reaction of intermediate 63 with either trifluoroacetic acid or cyclopropane carboxylic acid gives the syn -oxyaminated product 53 . Doping experiments confirmed the presence of both methyl trifluoroacetate and methyl cyclopropane carboxylate within the crude reaction mixture (see the Supporting Information for full details) consistent with this proposal.…”