Synthesis of 1-azaspiro[4.4]nonan-1-oxyls via intramolecular 1,3-dipolar cycloaddition
Keyword(s):
Sterically shielded nitroxides of the pyrrolidine series have shown the highest resistance to reduction. Here we report the synthesis of new pyrrolidine nitroxides from 5,5-dialkyl-1-pyrroline N-oxides via the introduction of a pent-4-enyl group to the nitrone carbon followed by an intramolecular 1,3-dipolar cycloaddition reaction and isoxazolidine ring opening. The kinetics of reduction of the new nitroxides with ascorbate were studied and compared to those of previously published (1S,2R,3′S,4′S,5′S,2″R)-dispiro[(2-hydroxymethyl)cyclopentan-1,2′-(3′,4′-di-tert-butoxy)pyrrolidine-5′,1″-(2″-hydroxymethyl)cyclopentane]-1′-oxyl (1).
2000 ◽
Vol 32
(7)
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pp. 431-434
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2018 ◽
Vol 16
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pp. 3-10
2018 ◽
Vol 6
(4)
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pp. 3928-3932
1977 ◽
Vol 42
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pp. 1278-1284
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1986 ◽
Vol 51
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pp. 2098-2108
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2006 ◽
Vol 71
(4)
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pp. 567-578
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