Synthesis of “Black Hole” 4,4'-Bipyridinium Cyclophane
XI Hai-Tao,b, SUN Xiao-Qiang*,b, WEI Hai-Linb, MENG Qia,
PAN Yia, HU Hong-Wena
Chin. J. Org. Chem. . 2007, (12): 1547 -1551 .