Syntheses of benzocyclooctenedione derivatives, cyclopenta[a]indanones and a benzo-anellated tetraquinane via sequential transformations of tricarbonyl(η<sup>6</sup>-1,2-dioxobenzocyclobutene)chromium(0)
作者:Michael Brands、Joachim Bruckmann、Carl Krüger、Holger Butenschön
DOI:10.1039/c39940000999
日期:——
Tricarbonyl(η6-1,2-dioxobenzocyclobutene)chromium(0)1 can be converted into benzocyclooctenedione derivatives 3, 7 and 8 as well as fused five-membered ring systems 2, 4 and 6 by addition of vinyl lithium derivatives and following double anionic oxy-Cope rearrangement under very mild reaction conditions (â78 °C); product ratios depend on the method of hydrolysis.
三羰基(η6-1,2-二氧代苯并环丁烯)铬(0)1可通过乙烯基锂衍生物的加成,并在非常温和的反应条件(-78°C)下进行双阴离子氧-Cope重排,转化为苯并环辛烯二酮衍生物3、7和8以及稠合五元环系统2、4和6;产物比例取决于水解方法。