TY - JOUR
T1 - Anion binding by metallo-receptors of 5,5′-dicarbamate-2,2′- bipyridine ligands
AU - Wu, Biao
AU - Yang, Jin
AU - Huang, Xiaojuan
AU - Li, Shaoguang
AU - Jia, Chuandong
AU - Yang, Xiao Juan
AU - Tang, Ning
AU - Janiak, Christoph
PY - 2011/6/7
Y1 - 2011/6/7
N2 - Three 5,5′-dicarbamate-2,2′-bipyridine ligands (L = L 1-L3) bearing ethyl, isopropyl or tert-butyl terminals, respectively, on the carbamate substituents were synthesized. Reaction of the ligands L with the transition metal ions M = Fe2+, Cu2+, Zn2+ or Ru2+ gave the complexes MLnX 2·xG (1-12, n = 1-3; X = Cl, NO3, ClO4, BF4, PF6, SO4; G = Et2O, DMSO, CH3OH, H2O), of which [Fe(L2) 3⊃SO4]·8.5H2O (2), [Fe(L 1)3⊃(BF4)2]·2CH 3OH (7), [Fe(L2)3⊃(Et2O) 2](BF4)2·2CH3OH (8), [ZnCl2(L1)][ZnCl2(L1)(DMSO)] ·2DMSO (9), [Zn(L1)3⊃(NO3) 2]·2H2O (10), [Zn(L2) 3⊃(ClO4)(Et2O)]ClO4· Et2O·2CH3OH·1.5H2O (11), and [Cu(L1)2(DMSO)](ClO4)2·2DMSO (12) were elucidated by single-crystal X-ray crystallography. In the complexes MLnX2·xG the metal ion is coordinated by n = 1, 2 or 3 chelating bipyridine moieties (with other anionic or solvent ligands for n = 1 and 2) depending on the transition metal and reaction conditions. Interestingly, the carbamate functionalities are involved in hydrogen bonding with various guests (anions or solvents), especially in the tris(chelate) complexes which feature the well-organized C3-clefts for effective guest inclusion. Moreover, the anion binding behavior of the pre-organized tris(chelate) complexes was investigated in solution by fluorescence titration using the emissive [RuL3]2+ moiety as a probe. The results show that fluorescent recognition of anion in solution can be achieved by the RuII complexes which exhibit good selectivities for SO 42-.
AB - Three 5,5′-dicarbamate-2,2′-bipyridine ligands (L = L 1-L3) bearing ethyl, isopropyl or tert-butyl terminals, respectively, on the carbamate substituents were synthesized. Reaction of the ligands L with the transition metal ions M = Fe2+, Cu2+, Zn2+ or Ru2+ gave the complexes MLnX 2·xG (1-12, n = 1-3; X = Cl, NO3, ClO4, BF4, PF6, SO4; G = Et2O, DMSO, CH3OH, H2O), of which [Fe(L2) 3⊃SO4]·8.5H2O (2), [Fe(L 1)3⊃(BF4)2]·2CH 3OH (7), [Fe(L2)3⊃(Et2O) 2](BF4)2·2CH3OH (8), [ZnCl2(L1)][ZnCl2(L1)(DMSO)] ·2DMSO (9), [Zn(L1)3⊃(NO3) 2]·2H2O (10), [Zn(L2) 3⊃(ClO4)(Et2O)]ClO4· Et2O·2CH3OH·1.5H2O (11), and [Cu(L1)2(DMSO)](ClO4)2·2DMSO (12) were elucidated by single-crystal X-ray crystallography. In the complexes MLnX2·xG the metal ion is coordinated by n = 1, 2 or 3 chelating bipyridine moieties (with other anionic or solvent ligands for n = 1 and 2) depending on the transition metal and reaction conditions. Interestingly, the carbamate functionalities are involved in hydrogen bonding with various guests (anions or solvents), especially in the tris(chelate) complexes which feature the well-organized C3-clefts for effective guest inclusion. Moreover, the anion binding behavior of the pre-organized tris(chelate) complexes was investigated in solution by fluorescence titration using the emissive [RuL3]2+ moiety as a probe. The results show that fluorescent recognition of anion in solution can be achieved by the RuII complexes which exhibit good selectivities for SO 42-.
UR - http://www.scopus.com/inward/record.url?scp=79957471857&partnerID=8YFLogxK
U2 - 10.1039/c0dt01561j
DO - 10.1039/c0dt01561j
M3 - Article
C2 - 21327244
AN - SCOPUS:79957471857
SN - 1477-9226
VL - 40
SP - 5687
EP - 5696
JO - Dalton Transactions
JF - Dalton Transactions
IS - 21
ER -