Synthesis, crystal structures and properties of the novel mononuclear copper(II) and tetranuclear cobalt(II) complexes with 3,6-bis-(3,5-dimethylpyrazolyl)-pyridazine

Abstract

A novel monomer copper(II) complex [Cu(L) 2 (SCN)] AE ClO 4 (1) and a tetranuclear cobalt(II) complex [Co 4 (L) 4 (N 3 ) 4 ](OH) 4 AE 2H 2 O (2)(L = 3,6-bis-(3,5-dimethylpyrazolyl)-pyridazine) have been synthesized and structurally characterized. Single crystal X-ray analyses show that the Cu(II) atom is in a distorted trigonal bipyramidal coordinated environment consisting of four N atoms of L and one N atom of SCN ) in complex (1), and the monomer is extended to a 1D chain by the weak intermolecular p...p stacking interactions. In the complex (2), four Co(II) atoms are linked by four bridging azido groups in l-1,1-N 3 (end-on) coordination mode to form a tetranuclear configuration. The fungicidal activity of the title compounds have been studied, and the results show that there are certain activities against several bacteria for the complexes and the ligand. Furthermore, two complexes exhibit blue emission fluoresce in the solid state at room temperature.

The effects of auxiliary ligands on the synthesis, crystal structures and properties of three complexes with a substituted pyridazine ligand

“…Firstly, it is found that complexes with this asymmetrical ligand tend not to assemble intriguing structures as previously observed for complexes with the symmetric ligand [3,6-di(3 0 ,5 0 -dimethyl-pyrazole)pyridazine] [16,23,28]; secondly, the auxiliary ligand plays an important role in the construction of crystal structures because the auxiliary ligand can provide non-coordinating bonds or/and it can act as bridging ligand; finally, by comparing the fungicidal activities of complexes (1) ,(2), and (3) with those of other complexes reported by our group, it may be observed that the antibacterial activities of the complexes are influenced by several different factors. …”

“…Complex (2) shows higher activities in respect of all of the epiphytes than the other compounds, and it is noteworthy that the activities against Physalospora piricola and Alternaria solani are 76% and 71%, respectively, much higher than those of free ligand and complexes (1) and (3), also much higher than those of [Co 4 L 4 0 (N 3 ) 4 ]. (OH) 4 .2H 2 O, where the ligand L 0 is 3,6-bis-(3,5-dimethylpyrazolyl)-pyridazine [23]. Although the activities of multinuclear complexes generally are higher than those of mononuclear ones [24][25][26], the binuclear Co(II) complex with an asymmetric pyridazine ligand has higher activities than the tetranuclear Table 6.…”

Synthesis, crystal structures, and biological activities of silver(I) and cobalt(II) complexes with an azole derivative ligand

“…The data indicate that complex (1) shows better activities against all the epiphytes than the other compounds. It is noteworthy that the activities against Physalospora piricola and Alternaria solani are 88% and 75%, respectively, much higher than that we have previously reported for [Cu(PPDMe) 2 (SCN)] Á ClO 4 and [Co 4 (PPDMe) 4 (N 3 )](OH) 4 Á 2H 2 O [11]. However, L and complex (2) exhibit lower fungicidal activities, which suggests that the metal plays a decisive role in the fungicidal activities.…”

“…In contrast, compared to the many reports on the anti-bacterial activity of Ag(I) complexes, there are few on their SOD activity. Accordingly, we have systematically studied the synthesis and properties of azole compounds and their complexes [11][12][13]. Herein Ag(I) and Co(II) complexes with 1-(imidazol-1-yl-methyl)-benzotriazole have been synthesized and their biological properties have been studied.…”

Syntheses, crystal structures and antibacterial activities of azido-bridged cobalt(III) complexes with Schiff bases

“…Recently, a large number of azido-bridged copper(II) and nickel(II) complexes with Schiff bases have been reported; however, the end-on azido-bridged polynuclear cobalt complexes are very few. Thus, a search in the Cambridge Crystallographic Database (version 5.31 with addenda up to February 26, 2010) [13] revealed that there are only fourteen end-on azido-bridged polynuclear cobalt complexes [14][15][16][17][18][19][20][21][22][23][24][25][26][27]. In the present paper, two new azido-bridged cobalt(III) complexes with Schiff bases 5-methoxy-2-[(2-morpholin-4-ylethylimino)methyl]phenol (HL1) and 2-ethoxy-6-[(2-isopropylaminoethylimino)methyl]phenol (HL2) (Scheme 1) have been reported.…”