Bromination–dehydrobromination of saturated 1,6-dioxaspiro[4.4]nonanes afforded a variety of naturally occurring 1,6-dioxaspiro[4.4]-nonenes and -nonadienes, such as 2–5 and 8, and can be applied to give unsaturated spirolactones, such as 27.

中文翻译：

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溴化-脱氢溴化途径生成一些天然存在的1,6-二氧杂螺[4.4]-壬烯和-壬二烯

饱和1,6-二氧杂螺溴化-脱溴化氢[4.4]壬烷，得到的天然存在的1,6-二氧杂螺各种[4.4] -nonenes和-nonadienes，如2 - 5和8，并且可以应用于以得到不饱和spirolactones如27。