Synthesis, Crystallographic and Spectral Characterization of a Cadmium Chloride Complex Containing a Novel Imidazo[1,5-a]Pyridine Derivative

Abstract

The reaction between 2-(2-amino-ethylamino)ethanol and pyridine-2-carbaldehyde in a 1 : 3 molar ratio gave 3-(pyridin-2-yl)-1-(pyridin-2-ylmethyl)imidazo[1,5-a]pyridine (PPIP) which was characterized by elemental analysis and spectroscopic methods. The study of CSD-deposited structures revealed that PPIP is a new derivative of imidazo[1,5-a]pyridine. The cadmium chloride complex of this ligand [Cd(PPIP)Cl 2 ][Cd(PPIP)Cl 2 ] ·3H 2 O (1) was prepared and identified by elemental analysis, FT-IR, Raman and 1 H NMR spectroscopy, and single-crystal X-ray diffraction. In the crystal structure of 1, there are two cadmium complexes with slightly different coordination bond lengths and angles. Also water molecules are incorporated in the crystal network. The geometry around the cadmium atom which is coordinated by two pyridine and one imine nitrogen atoms and two chloride ions is distorted square pyramidal. All bond lengths compare well with CSD averages of similar structures. The hydrogen bonds including O-H···Cl and O-H···O present in the crystal structure of 1 are also comparable to those in analogs.

Crystal Structure and Characterization of a New Eight Coordinated Cadmium Complex

“…22b, 23 We assigned all types of the vibrations for H 2 O molecules in the IR and Raman spectra of 1 but vibrations such as δ (H 2 O), ν (C=C) and γ (py) overlapped with vibrations due to ν (C=N imine ), ν s (COO) and δ (OCO), respectively. Information about the low-frequency vibrations of metal- were assigned to the ν (Cd-N) 25 and ν (Cd-O) 26 respectively.…”

Complexation to Cadmium(II) of a Tetradentate Ligand Resulting from the Condensation of 2-Pyridinecarbaldehyde with N-(2- Aminoethyl)propane-1,3-diamine

“…These modes are due to rotational oscillations of the water molecules restricted by interactions with neighboring atoms and they are classified into three types (wagging (ρ w ), twisting (ρ t ) and rocking (ρ r )) depending upon the direction of the principal axis of rotation [13,14]. δ (H 2 O) overlaps with ν (C=N imine ).…”

Spectral and Geometrical Study of Two Cadmium Complexes, mer-R,S-[Cd(aepn)2]X2(X: I-, Cl-, aepn: N-(2-Aminoethyl)-1,3-propanediamine) Supported by Solution Experiments

“…These modes are due to rotational oscillations of the water molecules restricted by interactions with neighboring atoms and they are classified into three types (wagging (ρ w ), twisting (ρ t ) and rocking (ρ r )) depending upon the direction of the principal axis of rotation. 19 In the IR and Raman spectra of 2, vibrations such as ν s (H 2 O), δ (H 2 O) and ρ w (H 2 O) overlapped with vibrations due to the ν as (NH 2 ), δ (NH 2 ) and ν (CdN) respectively.…”