TY - JOUR
T1 - Synthesis and characterization of luminescent zinc(II) and cadmium(II) complexes with N,S-chelating schiff base ligands
AU - Kawamoto, Tatsuya
AU - Nishiwaki, Masato
AU - Tsunekawa, Yasutaka
AU - Nozaki, Koichi
AU - Konno, Takumi
PY - 2008/4/21
Y1 - 2008/4/21
N2 - The reactions of zinc(II) acetate with a variety of 2-substituted benzothiazolines afforded tetrahedral mononuclear complexes with a N 2S2 donor set, [Zn(R-Ph-C(H)=N-C6H 4-S)2]. The obtained zinc(II) complexes can be divided into three groups based on the characteristics of the absorption spectra; Group 1 (R = 2,4,6-triMe (1), 2,6-diCl (2)) showing an intense band at 250-300 nm and a weak band at 400-450 nm, Group 2 (R = 4-Cl (3), H (4), 4-Et (5), 4-OMe (6)) showing two intense bands at 250-300 nm and a weak band at 400-450 nm, and Group 3 (R = 4-NMe2 (7), 4-NEt2 (8)) showing an intense band at 250-300 nm and two very intense bands at 350-450 nm. The Group 2 and Group 3 complexes exhibited a strong emission on irradiating with ultraviolet light while the Group 1 complexes were not emissive at room temperature. However, all the zinc(II) complexes were luminescent in CH2Cl2/toluene glass at 77 K, and their emission peak energies were found to correlate with the Hammett constant of the substituent at para position of a pendent phenyl ring in each complex. Similar reactions of cadmium(II) acetate with 2-substituted benzothiazolines were also carried out to synthesize corresponding cadmium(II) complexes. While [Cd(R-Ph-C(H)=N-C6H4-S)2] (R = 2,4,6-triMe (9)) with bulky substituents at ortho positions of a pendent phenyl ring had a tetrahedral mononuclear structure, other cadmium(II) complexes [Cd2(R-Ph-C(H)=N-C6H4-S)4] (R = 4-Et (10), 4-OMe (11), 4-NMe2 (12)) possessed S-bridged dinuclear structures. These cadmium(II) complexes, which are assumed to have a mononuclear structure in solution, showed photophysical properties similar to those of the corresponding zinc(II) complexes.
AB - The reactions of zinc(II) acetate with a variety of 2-substituted benzothiazolines afforded tetrahedral mononuclear complexes with a N 2S2 donor set, [Zn(R-Ph-C(H)=N-C6H 4-S)2]. The obtained zinc(II) complexes can be divided into three groups based on the characteristics of the absorption spectra; Group 1 (R = 2,4,6-triMe (1), 2,6-diCl (2)) showing an intense band at 250-300 nm and a weak band at 400-450 nm, Group 2 (R = 4-Cl (3), H (4), 4-Et (5), 4-OMe (6)) showing two intense bands at 250-300 nm and a weak band at 400-450 nm, and Group 3 (R = 4-NMe2 (7), 4-NEt2 (8)) showing an intense band at 250-300 nm and two very intense bands at 350-450 nm. The Group 2 and Group 3 complexes exhibited a strong emission on irradiating with ultraviolet light while the Group 1 complexes were not emissive at room temperature. However, all the zinc(II) complexes were luminescent in CH2Cl2/toluene glass at 77 K, and their emission peak energies were found to correlate with the Hammett constant of the substituent at para position of a pendent phenyl ring in each complex. Similar reactions of cadmium(II) acetate with 2-substituted benzothiazolines were also carried out to synthesize corresponding cadmium(II) complexes. While [Cd(R-Ph-C(H)=N-C6H4-S)2] (R = 2,4,6-triMe (9)) with bulky substituents at ortho positions of a pendent phenyl ring had a tetrahedral mononuclear structure, other cadmium(II) complexes [Cd2(R-Ph-C(H)=N-C6H4-S)4] (R = 4-Et (10), 4-OMe (11), 4-NMe2 (12)) possessed S-bridged dinuclear structures. These cadmium(II) complexes, which are assumed to have a mononuclear structure in solution, showed photophysical properties similar to those of the corresponding zinc(II) complexes.
UR - http://www.scopus.com/inward/record.url?scp=43349106173&partnerID=8YFLogxK
U2 - 10.1021/ic7020758
DO - 10.1021/ic7020758
M3 - 学術論文
C2 - 18345616
AN - SCOPUS:43349106173
SN - 0020-1669
VL - 47
SP - 3095
EP - 3104
JO - Inorganic Chemistry
JF - Inorganic Chemistry
IS - 8
ER -