BENZODIOXANS BY OXIDATIVE PHENOL COUPLING - SYNTHESIS OF SILYBIN
BENZODIOXANS BY OXIDATIVE PHENOL COUPLING - SYNTHESIS OF SILYBIN
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DOI：
10.1039/p19800000775
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发表时间：
1980-01-01
期刊：
影响因子：
--
通讯作者：
HANSEL, R
中科院分区：
文献类型：
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作者：
MERLINI, L;ZANAROTTI, A;HANSEL, R
在氧化银存在下，取代的儿茶酚与异丁香酚或松柏醇氧化偶联，得到2，3-反式-1，4-苯并二恶英。当邻苯二酚带有烷基取代基时，该反应具有高度的区域选择性，而在亲电取代基的情况下，该反应就更不具有区域选择性了。提出了一种自由基偶联机理。报道了以2R，3R-二氢栎素和松柏醇为原料，高产率地一步仿生合成天然黄烷素水飞蓟宾和异水飞蓟宾。
Oxidative coupling of substituted catechols with isoeugenol or coniferyl alcohol in the presence of silver oxide affords 2,3-trans-1,4-benzodioxans in good yield. The reaction is highly regioselective when the catechol bears an alkyl substituent, much less so in the case of an electrophilic one. A free-radical coupling mechanism is proposed. A 1-step biomimetic synthesis in high yield of the natural flavanolignans silybin and isosilybin from 2R,3R-dihydroquercetin and coniferyl alcohol is reported.