Ag4L2 nanocage as a building unit toward the construction of silver metal strings.
Self-assembly of AgNO 3 with the semirigid tetratopic ligands 1,2,4,5-tetrakis(benzoimidazol-1-ylmethyl)benzene (TBim) and 1,2,4,5-tetrakis(5,6-dimethylbenzimidazol-1-ylmethyl)benzene (TDMBim) afforded compounds [Ag 4(mu 4-TBim) 2(mu 2-eta (2)-NO 3) 2](NO 3) 2. (1)/ 2CH 2Cl 2.2CH 3OH ( 1mu (1)/ 2CH 2Cl 2.2CH 3OH) and [(NO 3 (-)) subset{Ag 4(mu 4-TDMBim) 2}][Ag(NO 3) 2](NO 3) 2.CH 2Cl 2.CH 3OH.4H 2O ( 2.CH 2Cl 2.CH 3OH.4H 2O), respectively. The structures of 1 and 2 were characterized by single-crystal X-ray diffraction analysis. Both compounds adopt a M 4L 2-type tetragonal metalloprismatic cage structure, [Ag 4(mu 4-L) 2] (4+), with strong intramolecular silver-silver contacts. Compound 1 is a discrete species, while compound 2 is a novel infinite chainlike supramolecular array involving silver metal strings assembled from a [Ag 4(mu 4-L) 2] (4+) nanocage and silver linkages. Thermogravimetric analyses of 1. (1)/ 2CH 2Cl 2.2CH 3OH and 2.CH 3OH.4H 2O indicate that the Ag 4L 2-cage structures of 1 and 2 both are thermally stable up to 330 degrees C. Results from an in situ (1)H NMR study of AgNO 3 and TDMBim in different molar ratios unambiguously revealed the successive self-organization process, in which self-organization of the molecular cage takes place initially followed by crystallization of the corresponding supramolecular arrays with silver metal strings.
Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan.
Jing-Yun
JY
Wu
Yu-Fang
YF
Lin
Chuan-Hung
CH
Chuang
Tien-Wen
TW
Tseng
Yuh-Sheng
YS
Wen
Kuang-Lieh
KL
Lu
D001562:Benzimidazoles / Q000138:chemical synthesis / Q000737:chemistry*; D018360:Crystallography, X-Ray; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008958:Models, Molecular; D049329:Nanostructures / Q000737:chemistry*; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D012835:Silver Nitrate / Q000737:chemistry*; D013816:Thermodynamics; D013818:Thermogravimetry
D001562:Benzimidazoles; D009942:Organometallic Compounds; C015158:5,6-dimethylbenzimidazole; D012835:Silver Nitrate