✍ Scribed by Sören Giese; F.G. West
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Tri-and tetrasubstimted 1,4-dien-3-oues 1 were treated with Lewis acid in the presence of tdethylsilane, furnishing either silyl euol ethers 4 or cyclopentanunes 5 in goud yields, depending upon wt~k-up conditions. This reaction is l~resumed to occur through oxyallyl intea'mndiate 3, which undergoes intermolecular hydride transfer and O-silylation to give 4. In most cases, only 2 expaiv, of silane was required, and catalytic amounts of Lewis acid could be used. Trieaone substrate 7 was found to undergo clean conversion to tricyclic ether 8, indicating fast capture of the oxyallyl intermediate by the pendant olefln.
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## Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable v
Benzamides with tethered acetal groups undergo reactions in CF(3)SO(3)H to give ring-fused isoindolinones by a cyclization cascade. The reaction initially forms an N-acyliminium ion which then gives the isoindolinone by the aza-Nazarov reaction. An unusual variant also cyclizes at the allylic positi
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