Regio/site-selective alkylation of substrates containing a <i>cis</i>-, 1,2- or 1,3-diol with ferric chloride and dipivaloylmethane as the catalytic system
作者:Jian Lv、Yu Liu、Jia-Jia Zhu、Dapeng Zou、Hai Dong
DOI:10.1039/c9gc04126e
日期:——
In this study, we reported the regio/site-selective alkylation of substrates containing a cis-, 1,2- or 1,3-diol with FeCl3 as a key catalyst. A catalytic system consisting of FeCl3 (0.01–0.1 equiv.) and dipivaloylmethane (FeCl3/dipivaloylmethane = 1/2) was used to catalyze the alkylation in the presence of a base. The produced selectivities and isolated yields were similar to those obtained by methods
在这项研究中,我们报道了含有顺式-,1,2-或1,3-二醇的底物的区域/位置选择性烷基化,其中FeCl 3为关键催化剂。由FeCl 3(0.01-0.1当量)和二戊酰基甲烷(FeCl 3 / dipivaloylmethane = 1/2)组成的催化体系用于在存在碱的情况下催化烷基化。在大多数情况下,所产生的选择性和分离的产率与使用相同量的FeL 3(L =酰基丙酮配体)作为催化剂的方法所获得的相似。先前报道的用于烷基化的FeL 3催化剂不可商购,并且必须在使用前合成。相反,FeCl 3苯二甲酰甲烷(Hdipm)和二甲戊酰甲烷(Hdipm)是实验室中非常普遍且廉价的无毒试剂,因此使该方法更加绿色且易于操作。机理研究首次证实,FeCl 3最初在乙腈中存在碱的情况下与两当量的Hdipm反应形成[Fe(dipm)3 ],然后在[[]之间形成五或六元环中间体。 Fe(dipm)3 ]和底物的两个羟