A direct method to synthesize lignan cyclobutanes and analogs via photoinduced electron transfer is presented. A variety of oxygenated alkenes are employed to furnish terminal or substituted cyclobutane adducts with complete regiocontrol, yielding cycloadducts with trans stereochemistry. Key to minimizing competing cycloreversion is the inclusion of an aromatic electron relay (ER). This method has been adapted to the synthesis of the natural products magnosalin and pellucidin A.
本文介绍了一种通过光诱导电子转移合成
木质素环丁烷及其类似物的直接方法。该方法采用了多种含氧烯烃,以提供具有完全区域控制的末端或取代
环丁烷加合物,从而产生具有反式立体
化学性质的环加合物。将芳香族电子中继器(ER)的加入是最大限度地减少竞争性环化反应的关键。这种方法已用于合成
天然产物木犀草素和佩鲁西丁 A。