A Facile Synthesis of a Spironitrone and a Study of Its Cycloaddition and Nucleophilic Addition Reactions

Abstract

The synthesis of spironitrone 5 via microwave-assisted intramolecular alkylation of bromo oxime 10 is reported. The bromo oxime is prepared by alkylation of methyl cyclohexanecarboxylate with 1,4-dibromobutane followed by conversion of the methyl ester to an oxime. Spironitrone 5 undergoes facile 1,3-dipolar cycloaddition to a range of olefins to form a range of spirocyclic isoxazolidines. Nucleophilic addition of several Grignard reagents to spironitrone 5 provided access to a series of alkyl-substituted spirohydroxylamines.

Key words

1,3-dipolar cycloaddition - spironitrones - microwave - Grignard reagents

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