Highly efficient intramolecular cyclizations of 2′-hydroxychalcones to 4-chloro-2<i>H</i>-chromenes under vilsmeier conditions
作者:Zhen-Hua Li、Cun Zheng、Wei-Ke Su
DOI:10.1002/jhet.5570450441
日期:2008.7
Highly efficient intramolecular cyclization and of 2′-hydroxychalcones to 4-chloro-2H-chromenes under Vilsmeier conditions have been developed. In comparison with the reported methods, studies carried out indicate that Vilsmeier reagent generated in situ from DMF and bis(trichloromethyl) carbonate (BTC) provides excellent chemselectivity, higher yields and avoids the formation of inorganic phosphorus
已经开发了在维尔斯迈尔条件下高效的分子内环化和2'-羟基查耳酮成4-氯-2 H-色烯的过程。与报道的方法相比,进行的研究表明,由DMF和碳酸二(三氯甲基)酯(BTC)原位生成的Vilsmeier试剂具有出色的化学选择性,更高的收率并避免了无机磷盐的形成。