Regioselective syntheses of 6-(1,1-dimethylallyl)- and 8-(3,3-dimethylallyl) chrysins
作者:Jean-Baptiste Daskiewicz、Christine Bayet、Denis Barron
DOI:10.1016/s0040-4020(02)00309-5
日期:2002.4
1-dimethylallyl)- and 8-(3,3-dimethylallyl) chrysins have been designed. Claisen rearrangement of protected 5-O-(3,3-dimethylallyl) chrysin in N,N-diethylaniline at 200–217°C gave selective access to the 8-(3,3-dimethylallyl) isomer. Similar rearrangement in N,N-diethylbutylamine at 140–160°C, or in cycloheptane/Eu(fod)3 at 100°C, led to the formation of the 6-(1,1-dimethylallyl) isomer. Four different
已经设计了6-(1,1-二甲基烯丙基)-和8-(3,3-二甲基烯丙基)chrysins的第一个区域选择性合成。在200–217°C下,N,N-二乙基苯胺中受保护的5- O-(3,3-二甲基烯丙基)胰蛋白酶的Claisen重排可选择性地进入8-(3,3-二甲基烯丙基)异构体。在140-160°C的N,N-二乙基丁胺中或在100°C的环庚烷/ Eu(fod)3中进行类似的重排,导致了6-(1,1-二甲基烯丙基)异构体的形成。比较了针对菊花链7位的四个不同的保护基,发现它们遵循感兴趣的顺序Bz> MOM> TBDPS> MEM。