Stepwise Synthesis of Low-Symmetry Hexacationic Pyridinium Organic Cages
Jin-Xin Wang1,2, Shao-Chuan Li2, Li-Xuan Cai2
1College of Chemistry, Fuzhou University, Fuzhou, Fujian 350108, People's Republic of China.
Abstract:
An efficient approach was developed for the synthesis of the well-known BlueCage by pre-bridging two 2,4,6-tris(4-pyridyl)-1,3,5-triazine (TPT) panels with one linker followed by cage formation in a much improved yield and shortened reaction time. Such a stepwise methodology was further applied to synthesize three new pyridinium organic cages, C2, C3, and C4, where the low-symmetry cages C3 and C4 with angled panels demonstrated better recognition properties toward 1,1'-bi-2-naphthol (BINOL) than the high-symmetry analogue C2 featuring parallel platforms.
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