Enolethers vinyl ethers

As an extension of this work, photoinduced [2+2]-cycloadditions of 1-acetylisatin (13) with cyclic enolethers (furan, benzofuran, 2-phenylfuran, 8-methoxypsoralen), and acyclic enolethers (//-butyl vinyl ether and vinyl acetate) were investigated which afforded the spiro-oxetanes in high yields (82-96%) and with high regio- and diastereoselectivity (Sch. 4) [19]. Treatment of the furan-derived oxetane 15 with acid resulted in oxetane ring opening and yielded the 3-(furan-3-yl)indole derivative 16. 

Allyl enolethers Allyl vinyl ethers l,4-Diyn-3-ones... 

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