Aziridines, reactions with alkylidene

Reactions of Aziridines, 4-Oxazolines, and Their Derivatives with Alkylidene Phosphoranes and Phosphorus(III) Nucleophiles... 

Rings containing Nitrogen. - The reactions of aziridines with alkylidene-phosphoranes and with phosphorus(III) nucleophiles and the reactions of... 

The y-lactam 110 is prepared by the reaction of the lithium silyl-substituted ynolate 105 with the aziridine 108 activated by a p-toluenesulfonyl group. The initial product is the enolate 109, which can be acidified to yield the a-silyl-y-lactam 110. Intermediate 109 can be trapped by aldehydes to afford the a-alkylidene-y-lactams 111 via a Peterson reaction (equation 45) . These reactions may be considered to be formal [3 + 2] cycloadditions as well as tandem reactions involving nucleophilic ring opening and cyclization. 

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