Artikel
Synthesis of Methylenecyclobutenes by [2+2] Cycloaddition of Allene Ethers and Alkyne
Methylenecyclobutenes are synthesized via thermal conditions between allene ethers and alkyne and successfully transformed to other four-membered ring compounds. This strategy provides a series of methylenecyclobutenes in moderate yields with broad functional groups.
Abstract
Methylenecyclobutenes are useful precursors to provide other organic compounds. We report intermolecular [2+2] cycloaddition of allene ethers and alkynes at 100 °C, which gives methylenecyclobutenes in 50–60 % yields. The reaction does not require any metal catalyst and shows broad substrate scope, high regioselectivity and high stereoselectivity.
![Synthesis of Methylenecyclobutenes by [2+2] Cycloaddition of Allene Ethers and Alkyne](/_next/image?url=%2F_next%2Fstatic%2Fmedia%2Fplaceholder.5ca6fc18.png&w=256&q=75)
![Synthesis of Methylenecyclobutenes by [2+2] Cycloaddition of Allene Ethers and Alkyne](/_next/image?url=https%3A%2F%2Fcdn.gdch.de%2Fprod%2Fnadc20264158444_fig_0001_a_36fd5c002c.png&w=256&q=75)
![Synthesis of Methylenecyclobutenes by [2+2] Cycloaddition of Allene Ethers and Alkyne](/_next/image?url=https%3A%2F%2Fcdn.gdch.de%2Fprod%2Fnadc20264158499_fig_0001_a_8463b1bf14.png&w=256&q=75)
![Synthesis of Methylenecyclobutenes by [2+2] Cycloaddition of Allene Ethers and Alkyne](/_next/image?url=https%3A%2F%2Fcdn.gdch.de%2Fprod%2Fnadc20264158504_gra_0001_a_6653df00f8.png&w=256&q=75)
