Synthesis of 1,8-anthraquinone functionalized aza 18/20-crown-5 macrocycles and their chromogenic ion-pair recognition of hydroxides in DMSO
摘要:
Two N3O3 macrocyclic compounds with rigid chromogenic 1,8-dihydroxylenanthraquione and flexible diethylenetriamine/dipropenetriamine (L1 and L2), were synthesized and characterized. L1/L2 can interact with alkaline, alkaline-earth, as well as Zn2+, Pb2+, and Al3+ chloride/perchloride evidenced by their DPV change and H-1 NMR spectra. Unexpectedly, both L1 and L2 can show chromogenic response to Na+, K+, and TBA(+) hydroxide (but not LiOH). Large cavity L2 can show chromic response to Ca(OH)(2) and Ba(OH)(2), but L1 can only respond to Ca(OH)(2) in DMSO. L1 and L2 form 1:1 and 2:1 (Host:Guest) complex respectively with NaCl, NaOH, TBAOH in DMF/DMSO. Both hosts bind smaller Zn2+ and Al3+ in 2:1 in DMSO. L2 can form L2 center dot TBAOH greenish yellow complex that gradually transformed to red L2(2)center dot TBAOH in two steps in DMSO. Different from other macrocycles, L1 and L2 are ion-pair hosts that recognize cation and OH- via carbonyl groups.