Mesityllithium and p-(dimethylamino)phenyllithium for the selective alternate trilithiation of the hexaphenylbenzene framework
作者:Tatsuo Kojima、Shuichi Hiraoka
DOI:10.1039/c4cc04520c
日期:——
We report mesityllithium and p-(dimethylamino)phenyllithium as new valuable lithiating reagents, which realize Br/Li exchange reaction of bromoarenes at relatively high temperature in THF. With these reagents, we established the general and practical protocols for the selective alternate trilithiation of the hexaphenylbenzene framework.
Selective Alternate Derivatization of the Hexaphenylbenzene Framework through a Thermodynamically Controlled Halogen Dance
作者:Tatsuo Kojima、Shuichi Hiraoka
DOI:10.1021/ol500041j
日期:2014.2.7
We report a practical synthetic protocol and mechanistic details for the selective alternate derivatization of the hexaphenylbenzene (HPB) framework through a thermodynamically controlled halogen dance. The stability of the alternately trilithiated species of HPB is interpreted by the through-space interaction at the ipso-carbons of the phenyl groups of the HPB framework. By using this approach, C-3-symmetric and lower-symmetric HPB derivatives possessing two or three kinds of substituents on the periphery have become easily and practically available.