A practical and robust photo FriedelâCrafts acylation of naphthoquinones is described. Although the reaction proceeds slowly in sunlight, the optimised conditions offer a substantial improvement to those already reported, by the utilisation of a more reliable and practical âsun-mimickingâ light source, a less hazardous solvent system (trifluorotoluene) and faster reaction times. Using these conditions, the reaction scope has been expanded to include functionalised aldehyde and naphthoquinone substrates, affording the desired photo-products in acceptable to excellent yields (17â81%). Factors influencing the regiochemistry of the photo FriedelâCrafts reaction on unsymmetrical naphthoquinones have also been investigated.
本文介绍了一种实用而可靠的
萘醌光弗里德酰化反应。虽然该反应在阳光下进行得很慢,但优化后的条件与已报道的条件相比有了很大改进,因为它利用了更可靠、更实用的 "模拟太阳 "光源、危害更小的溶剂系统(
三氟甲苯)以及更快的反应时间。利用这些条件,反应范围扩大到包括官能化醛和
萘醌底物,以可接受到极好的收率(17%-81%)获得所需的光反应产物。此外,还研究了影响不对称
萘醌的光弗里德卡夫斯反应的区域
化学性质的因素。