11681901 |
Kingsley S, Chandrasekhar V, Incarvito CD, Lam MK, Rheingold AL: Tethered pyrazolyl phosphinate: pyrazolyl-N- and phosphoryl-O-metal coordination in Ph (2) P (O)[OCH (2) CH (2)(3,5-Me (2) Pz)]. Inorg Chem. 2001 Nov 5;40(23):5890-6. Phosphorus pyrazolides, P (O)(3,5-Me (2) Pz)(3) or RP (E)(3,5-Me (2) Pz)(2) [E = S or O, R = Me or Ph], are hydrolytically sensitive particularly upon interaction with transition metal ions. In this paper, we report a new tethered pyrazolyl phosphinate, Ph (2) P (O)[OCH (2) CH (2)(3,5-Me (2) Pz)] DPEP (1), where the pyrazolyl group is separated from the phosphorus by means of an ethyleneoxy spacer. 1 has two potential coordination sites in the form of a phosphoryl oxygen atom and a pyrazolyl nitrogen atom. 1 forms hydrolytically stable complexes, (DPEP-CoCl (2))(n)(2), (DPEP)(2)-CuCl (2) (3), (DPEP-ZnCl (2))(n )(4), and (DPEP)(2)-PdCl (2) (5). The cobalt (II) and the zinc (II) complexes 2 and 4 show a zigzag polymeric structure in the solid state with a tetrahedral coordination geometry around the metal ion; the ligand DPEP coordinates through its phosphoryl oxygen and the pyrazolyl nitrogen to two neighboring metal ions and functions as a bridging ligand to form the polymeric structure. In contrast to 2 and 4, the copper (II) and the palladium (II) complexes 3 and 5 show a square-planar geometry around the metal ion. Exclusive coordination through the pyrazolyl nitrogens of the ligand 1 is observed. An extensive supramolecular sheetlike two-dimensional polymeric network is observed in the solid-state structures of 3 and 5 as a result of two weak interactions: (a) an intermolecular C-H- - -O interaction involving the phosphoryl oxygen and an aromatic C-H and (b) a pi-pi face-to-face stacking interaction between the phenyl groups of two adjacent molecules. |
1(0,0,0,1) |