β-Phosphorylated five membered ring nitroxides, a new class of stable nitroxides. 1. Synthesis by Reaction. of dialkylphosphites with 1-pyrroline-n-oxides.

“…[19] By using this last condition (Scheme 2), the reaction of nitrone 4 with dialkyl esters 5a-c at 40°C gave the N-hydroxy-phosphonates 6a,b in quantitative yields whereas the bulky dibenzyl derivative 6c was only obtained in a moderate yield (47 %). Scheme 2. The N-OH group is generally reduced by hydrogenolysis over Pd/C, [15,18] and even better in the presence of aqueous HCl.…”

Section: Direct Addition Of Nucleophilesmentioning

confidence: 99%

Synthesis of Amino‐L‐Lyxose Phosphonates as Fucosyl‐Phosphate Mimics

et al. 2006

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Some reactions of nitrone 4 are described, namely the nucleophilic addition of dialkyl phosphites, HOP(OR)2, 5a–c or of diethyl methylphosphonate 8 and the dipolar [2+3] cycloaddition of vinylphosphonate 11. Chemical transformations led to 4‐amino‐L‐fucose derivatives bearing a phosphonate group in the 1α position linked to the pyrrolidine ring through a chain of 0–2 carbon atoms. The target compounds proved to be good‐to‐excellent α‐L‐fucosidase inhibitors. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

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“…Specifically, nitroxides 8 and 10 were formed by the spin trapping of methyl and phenyl radicals, respectively, by an interesting, newˇ-phosphityl nitrone. 57 For completeness, the multi-step route to 8 devised by Tordo and co-workers 58,59 is also included. a BO ž and BP Ł refer to hydrogen abstraction by tert-butoxyl radicals and photoexcited benzophenone, respectively.…”

Section: Routes To the B-phosphorus Nitroxidesmentioning

confidence: 99%

ESR of newβ-phosphorus nitroxides from aldo- and keto-nitrones

Haire

Janzen

Hrvoic³

1999

Magn. Reson. Chem.

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This investigation deals mainly with the synthesis of new phosphorus–nitroxide free radicals. Nitroxides with a β‐31P group were synthesized from the aldo‐nitrones α‐phenyl‐N‐tert‐butylnitrone and 5,5‐dimethyl‐1‐pyrroline‐N‐oxide (DMPO) as well as the keto‐nitrones 2,5,5‐trimethyl‐1‐pyrroline‐N‐oxide (2,5,5‐M3PO) and 2‐phenyl‐5,5‐dimethyl‐1‐pyrroline‐N‐oxide (2‐Ph‐DMPO). Three different routes were explored. The first two routes involved nitronyl spin trapping of phosphorus‐centred radicals generated thermally or photochemically by hydrogen abstraction by tert‐butoxyl radicals from di‐tert‐butyl peroxyoxalate or from photoexcited benzophenone, respectively. The third approach used the addition of phosphorus anions (generated by the strong, hindered base lithium diisopropylamide) to the nitrones and subsequent one‐electron oxidation to the corresponding nitroxides. The most novel feature of the work presented here may be the synthesis of β‐phosphoranyl [P(OR)4] nitroxide spin adducts. For comparison purposes the related β‐phosphityl [P(O)(OR)2] nitroxides were also assembled and characterized by ESR spectroscopy. Copyright © 1999 John Wiley & Sons, Ltd.

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β-Phosphorylated five membered ring nitroxides, a new class of stable nitroxides. 1. Synthesis by Reaction. of dialkylphosphites with 1-pyrroline-n-oxides.

Cited by 26 publications

References 10 publications

Synthetic Methods for Azaheterocyclic Phosphonates and Their Biological Activity

Synthetic Methods for Azaheterocyclic Phosphonates and Their Biological Activity

Synthesis of Amino‐L‐Lyxose Phosphonates as Fucosyl‐Phosphate Mimics

ESR of newβ-phosphorus nitroxides from aldo- and keto-nitrones

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