Preparation and rearrangement of N-vinyl nitrones: Synthesis of spiroisoxazolines and fluorene-tethered isoxazoles
N-Vinyl nitrones derived from fluorenone have been prepared via a copper-mediated coupling between fluorenone oxime and vinyl boronic acids. These compounds undergo subsequent rearrangement and addition reactions that are distinct from the traditional [3 + 2] cycloaddition reactivity of nitrones. Thermal rearrangements of fluorenone N-vinyl nitrones give spiroisoxazolines, while treatment with alkynes provides fluorene-tethered isoxazoles. The scope and limitations of the preparation of fluorenone N-vinyl nitrones and their subsequent rearrangement and addition reactions are discussed.
Mo, Dong-Liang,Wink, Donald A.,Anderson, Laura L.
supporting information
p. 5180 - 5183,4
(2012/12/12)
SYNTHESIS OF 2-NITROALKYL PHENYL SELENIDES AND THEIR CONVERSION TO NITROALKENES
Treatment of alkenes with benzeneselenenyl bromide followed by addition of silver nitrite provided a mixture of 2-nitroalkyl and 2-hydroxyalkyl phenyl selenides.Oxidation of the former selenides with hydrogen peroxide gave nitroalkenes in 90-93 percent yields.
SYNTHESIS OF CONJUGATED NITROALKENES VIA NITROSELENENYLATION OF ALKENES
Addition of silver nitrite to 2-bromoalkyl phenyl selenide in the presence of mercury(II)chloride afforded 2-nitroalkyl phenyl selenide, wich upon oxidative deselenenylation provided the conjugated nitroalkene in excellent yield.