Strain-Activated Diels–Alder Trapping of 1,2-Cyclohexadienes: Intramolecular Capture by Pendent Furans
作者:Verner A. Lofstrand、Kyle C. McIntosh、Yaseen A. Almehmadi、F. G. West
DOI:10.1021/acs.orglett.9b02085
日期:2019.8.16
Intramolecular [4 + 2] cycloaddition reactions of substituted 1,2-cyclohexadienes with pendent furans enables the synthesis of complex tetracyclic scaffolds in a single step under mild conditions. All Diels–Alder cycloadducts were obtained as single diastereomers, assigned as the endo isomer. Substrates were easily assembled via Stork–Danheiser alkylation of 3-ethoxy-2-bromocyclohex-2-enone to accommodate
取代的1,2-环己二烯与侧基呋喃的分子内[4 + 2]环加成反应可在温和条件下一步合成复杂的四环骨架。所有Diels–Alder环加合物均作为单一非对映异构体获得,被指定为内聚异构体。可以通过3-乙氧基-2-溴环己基-2-烯酮的Stork–Danheiser烷基化轻松组装基板,以容纳一系列的系链和呋喃捕集阱。烯醇乙酸酯部分的切割导致室温的狄尔斯-阿尔德环还原为拴系的呋喃基环己烯酮。