Regiospecific α-substitution of crotonic esters synthesis of naturally occurring derivatives of 6-ethyljuglone
作者:Brigitte Caron、Paul Brassard
DOI:10.1016/s0040-4020(01)87099-x
日期:1991.1
Methyl β-methoxycrotonate is alkylated regiospecifically, through the anion, in the α-position. Enolsilylation of the resulting β,γ-unsaturated ester affords the corresponding 1,1,2,3-tetrasubstituted butadiene. Cycloaddition of the latter to the appropriate halogenated benzoquinone, followed by various transformations, provides the first recorded syntheses of several natural products derived from
β-甲氧基巴豆酸甲酯通过阴离子在α位上区域特异性地烷基化。所得β,γ-不饱和酯的烯醇化得到相应的1,1,2,3-四取代丁二烯。后者与适当的卤代苯醌进行环加成反应,然后进行各种转化,首次记录了衍生自6-乙基-7-甲氧基juglone的几种天然产物的合成。