Laccase-Catalyzed Domino Reactions between Hydroquinones and Cyclic 1,3-Dicarbonyls for the Regioselective Synthesis of Substituted <i>p</i>-Benzoquinones
作者:Szilvia Hajdok、Jürgen Conrad、Uwe Beifuss
DOI:10.1021/jo202082v
日期:2012.1.6
obtained in yields ranging from 39% to 98% by laccase-catalyzed dominoreactions between hydroquinones and cyclic 1,3-dicarbonyls using aerial oxygen as the oxidant. In almost all reactions bis-adducts with two adjacent 1,3-dicarbonyl substituents on the quinone moiety were formed selectively. The transformations can be regarded as domino oxidation/1,4-addition/oxidation/1,4-addition/oxidation processes
通过使用空气中的氧气作为氧化剂,对苯二酚和环状1,3-二羰基化合物进行漆酶催化的多米诺反应,可以以39%至98%的产率获得高度取代的对苯醌。在几乎所有反应中,选择性地形成在醌部分上具有两个相邻的1,3-二羰基取代基的双加合物。所述转化可被视为多米诺氧化/ 1,4-加成/氧化/ 1,4-加成/氧化过程。以未取代的对苯二酚为底物,分离出2,3-二取代的对苯醌。双加合物也仅在与单取代对苯二酚反应后形成。在几乎所有情况下,2,3,5-三取代的p获得了-苯醌。当使用2,3-二取代对苯二酚作为起始原料时,分离出2,3,5,6-四取代对苯醌。通过NMR光谱方法已经实现了所有产物的明确结构解析,包括长距离耦合C═O碳的自旋模式分析和1 H NMR光谱中的13 C卫星分析。