1. Addition of zinc homoenoates to acetylenic esters and amides: a formal (3 + 2) cycloaddition
- Author
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Crimmins, Michael T., Nantermet, Philippe G., Trotter, B. Wesley, Vallin, Isabelle M., Watson, Paul S., McKerlie, Lynne A., Reinhold, Tracy L., Cheung, Adrian Wai-Hing, Stetson, Katherine A., Dedopoulou, Dimitra, and Gray, Jeffrey L.
- Subjects
Organic compounds -- Synthesis ,Alicyclic compounds -- Research ,Ketones -- Research ,Copper compounds -- Usage ,Acetylene -- Research ,Carbonyl compounds -- Research ,Biological sciences ,Chemistry - Abstract
The copper-catalyzed conjugate addition-cyclization of zinc homoenolates to alkynic esters and amides constitutes a formal (3 + 2) cycloaddition that allows access to functionalized cyclopentenones. The enolate is prepared by ultrasonication of ((ethoxycyclopropyl)oxy)trimethylsilane and zinc chloride in ether, while the acetylenes are derived from the reaction of the lithium acetylide of propiolates or amides with aldehydes. The cycloaddition process is high-yielding and highly tolerant of such sensitive functional groups as epoxides, acetals, silyl ethers and furans.
- Published
- 1993