Unique asymmetric (CuII4) double-stranded helicate from a hexadentate piperazine-based ligand: ligand conformation isomerism upon coordination.
In methanol, the reaction of Cu(ClO(4))(2).6H(2)O and a sterically constrained piperazine imine phenol ligand (H(2)L), in the presence of NEt(3), affords a novel tetranuclear copper(II) complex of formula [Cu(II)(4)(mu(3)-L)(2)(mu-OH)(2)(H(2)O)(2)](ClO(4))(2).H(2)O (1). The X-ray structure of this complex shows an elongated Cu(4) quasi-tetrahedron coordinated to two hexadentate chair-(e,a)-mu(3)-piperazine bridging ligands. Variable-temperature magnetic studies show an S(t) = 0 spin ground state resulting from antiferromagnetic interactions between Cu(II) ions within the complex.
Paital
Alok Ranjan
AR
Department of Chemistry, Indian Institute of Technology, Kharagpur 721 302, India.
Nanda
Prasant Kumar
PK
Das
Sunirban
S
Aromí
Guillem
G
Ray
Debashis
D
D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D008024:Ligands; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D010879:Piperazines / Q000737:chemistry*; D013237:Stereoisomerism; D013696:Temperature
D008024:Ligands; D009942:Organometallic Compounds; D010879:Piperazines; D003300:Copper