Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China.
Org Lett. 2012 Jun 1;14(11):2710-3. doi: 10.1021/ol300908g. Epub 2012 May 15.
Phenol-derived electrophiles are favorable substrates because phenols are naturally abundant or can be readily prepared from other aromatic compounds. However, the cleavage of aromatic C-O bonds is a great challenge because of their high energy. K(2)CO(3)-catalyzed intramolecular cyclization of 1-(2-alkoxyphenyl)-3-akylpropane-1,3-dione and 3-(alkylimino)-1-(2-methoxyphenyl)-2-methylpropan-1-one derivatives via the selective cleavage of aromatic C-O bonds is reported. The corresponding chromone and 4-quinolone derivatives were obtained in reasonable yields.
酚衍生的亲电试剂是有利的底物，因为酚类物质在自然界中丰富存在，或者可以很容易地从其他芳香族化合物中制备得到。然而，由于芳香族 C-O 键的能量很高，因此它们的断裂是一个巨大的挑战。本文报道了 K2CO3 催化的 1-(2-烷氧基苯基)-3-烷基丙烷-1,3-二酮和 3-(烷基亚氨基)-1-(2-甲氧基苯基)-2-甲基-1-丙酮衍生物通过选择性断裂芳香族 C-O 键的分子内环化反应。以合理的产率得到了相应的色酮和 4-喹诺酮衍生物。
