作者:Charles B. de Koning、Joseph P. Michael、Willem A. L. van Otterlo
DOI:10.1039/a908367g
日期:——
Syntheses of the oxygen analogues 6, 7 and 8 of the michellamines 1 and korupensamines 2 are described. Racemic 5-iodo-6,8-dimethoxy-trans-1,3-dimethylisochromane 10 was synthesised in eleven steps from 2,4-dimethoxybenzaldehyde in an overall yield of 51%. The isopropoxy analogue 11 was synthesised in a similar manner. Isochromane 10 was coupled using Suzuki methodology with 4-isopropoxy-5-methoxy-7-methylnaphthalene-1-boronic acid 9 to produce 7 in 96% yield. This was converted in good yield into the desired product 6 by oxidative dimerisation followed by reduction of the cross-conjugated ene-dione intermediate 45.
本文介绍了氧类似物 6、7 和 8 的合成过程。外消旋 5-碘-6,8-二甲氧基-反式-1,3-二甲基异色胺 10 是由 2,4-二甲氧基苯甲醛经 11 个步骤合成的,总收率为 51%。异丙氧基类似物 11 的合成方法与此类似。用铃木法将异铬烷 10 与 4-异丙氧基-5-甲氧基-7-甲基萘-1-硼酸 9 结合,制得 7,收率为 96%。通过氧化二聚化,然后还原交叉共轭的烯二酮中间体 45,以良好的收率将其转化为所需的产品 6。