シクロヘプタジエン類の異性化反応

抄録

We have previously reported that a new intermolecular [3+2+2]cycloaddition reaction of ethyl cyclopropylideneacetate with alkynes proceeded in the presence of a Ni(0)/PPh₃ catalyst, and cycloheptadiene derivatives were obtained. However, in the reaction of 1-cyclopropylidene-2-propanone with alkynes, a cycloheptatriene derivative was obtained instead of the cycloheptadiene derivative. It was anticipated that the isomerization of the cycloheptadiene derivative led to the formation of the cycloheptatriene derivative. In this study, we examined the isomerization of cycloheptadiene derivatives under acidic, basic and thermal conditions, and the progress of the isomerization was observed.

fig.1