Structure and spectra of dichloro(hydroxy-methoxy-di(2-pyridyl)methane)copper(II)

Influence of the Bridging Group of Cross-Conjugated Nitrogenous Bases on the Spectra and Structure of Solvatochromic Mixed-Ligand Copper(II) Chelates Containing β-Ketoenols

“…An sp 3 -hybridized carbon atom connecting the pyridyl groups and trans to the copper(II) ion accommodates 23 the adoption of the boat conformation by the chelate ring and facilitates the approach of the etheric oxygen to copper. These indicate that the resulting di(2-pyridyl)methoxymethanol acts as tridentate ligand as in Cu(dpC(OH)OCH 3 )Cl 2 …”

“…It is known that dpk (pyCOpy) upon chelation becomes susceptible to nucleophilic attack by protic molecules, 9 and, as recent investigations confirmed, the coordinated ketone reacts with alcohols to yield the corresponding semiacetals. 22 Thus the formulas [Cu(β)dpC(OH)OR]ClO 4 and [Cu(β)dpC(OH) 2 ]ClO 4 are more appropriate (Table 1). The predominant reaction of chelated 2,2′-dipyridylamine is deprotonation.…”

Influence of the Bridging Group of Cross-Conjugated Nitrogenous Bases on the Spectra and Structure of Solvatochromic Mixed-Ligand Copper(II) Chelates Containing β-Ketoenols

“…An sp 3 -hybridized carbon atom connecting the pyridyl groups and trans to the copper(II) ion accommodates 23 the adoption of the boat conformation by the chelate ring and facilitates the approach of the etheric oxygen to copper. These indicate that the resulting di(2-pyridyl)methoxymethanol acts as tridentate ligand as in Cu(dpC(OH)OCH 3 )Cl 2 …”

“…It is known that dpk (pyCOpy) upon chelation becomes susceptible to nucleophilic attack by protic molecules, 9 and, as recent investigations confirmed, the coordinated ketone reacts with alcohols to yield the corresponding semiacetals. 22 Thus the formulas [Cu(β)dpC(OH)OR]ClO 4 and [Cu(β)dpC(OH) 2 ]ClO 4 are more appropriate (Table 1). The predominant reaction of chelated 2,2′-dipyridylamine is deprotonation.…”

Copper(II)-Promoted Chemical Transformations of 3-Substituted 5-(2′-Pyridyl)-1,4-benzodiazepin-2-one Derivatives. Crystal Structures and Spectroscopic Characterisation of Metal Complexes

“…On the other hand coupled Cu−Cl and Cu−N bands could also be expected. The band at 364 cm −1 may be assigned to the ν(Cu−O) vibration, since it was found that ν(Cu−O) > ν(Cu−N) for this kind of metal complex 31,32. The situation is more complicated in complex 7 , where the internal deformation modes of the acetate ligand also falls into the same spectral region as the metal‐ligand vibrations.…”

Synthesis of Pt(dpk)Cl4 and the Reversible Hydration to Pt(dpk-O-OH)Cl3·H-phenCl: X-ray, Spectroscopic, and Electrochemical Characterization

“…In most cases where the metal:dpk ratio is 1:1, the ketone on the dpk ligand either does not hydrate at all or it remains a true gem -diol. One possible exception to this was reported with a copper(II) dpk compound in which the ketone had reacted with a methanol molecule in a fashion similar to hydration . In that case, the methoxy oxygen appeared to cyclometalate and coordinate with the metal center in an axial position.…”

“…In compound 2 the bond angle for C(21)−C(1)−C(11) (py−CO−py) is 106.49°. For this reason, many research groups have erroneously proposed that the metal-promoted hydration of the ketone in the dpk ligand is solely a result of steric strain on the carbonyl carbon, a desire of the carbonyl carbon to change from sp 2 hybridization to sp 3 hybridization to better accommodate the smaller bond agle. ,,,,,, An explanation for this behavior based on molecular models is that the bond strain and steric interaction within the system of the carbonyl carbon causes a transition from an sp 2 → sp 3 orbital hybridization upon ligation of the pyridyl rings. ,,,,,, In other words, the addition of the carbonyl spacer between the two pyridyl rings causes the chelation angle to be too large. As a result, the pyridyl rings fold up and pull in.…”

Influence of the Bridging Group of Cross-Conjugated Nitrogenous Bases on the Spectra and Structure of Solvatochromic Mixed-Ligand Copper(II) Chelates Containing β-Ketoenols

“…An sp 3 -hybridized carbon atom connecting the pyridyl groups and trans to the copper(II) ion accommodates 23 the adoption of the boat conformation by the chelate ring and facilitates the approach of the etheric oxygen to copper. These indicate that the resulting di(2-pyridyl)methoxymethanol acts as tridentate ligand as in Cu(dpC(OH)OCH 3 )Cl 2 …”

“…It is known that dpk (pyCOpy) upon chelation becomes susceptible to nucleophilic attack by protic molecules, 9 and, as recent investigations confirmed, the coordinated ketone reacts with alcohols to yield the corresponding semiacetals. 22 Thus the formulas [Cu(β)dpC(OH)OR]ClO 4 and [Cu(β)dpC(OH) 2 ]ClO 4 are more appropriate (Table 1). The predominant reaction of chelated 2,2′-dipyridylamine is deprotonation.…”

Copper(II)-Promoted Chemical Transformations of 3-Substituted 5-(2′-Pyridyl)-1,4-benzodiazepin-2-one Derivatives. Crystal Structures and Spectroscopic Characterisation of Metal Complexes

“…On the other hand coupled Cu−Cl and Cu−N bands could also be expected. The band at 364 cm −1 may be assigned to the ν(Cu−O) vibration, since it was found that ν(Cu−O) > ν(Cu−N) for this kind of metal complex 31,32. The situation is more complicated in complex 7 , where the internal deformation modes of the acetate ligand also falls into the same spectral region as the metal‐ligand vibrations.…”

Synthesis of Pt(dpk)Cl4 and the Reversible Hydration to Pt(dpk-O-OH)Cl3·H-phenCl: X-ray, Spectroscopic, and Electrochemical Characterization

“…In most cases where the metal:dpk ratio is 1:1, the ketone on the dpk ligand either does not hydrate at all or it remains a true gem -diol. One possible exception to this was reported with a copper(II) dpk compound in which the ketone had reacted with a methanol molecule in a fashion similar to hydration . In that case, the methoxy oxygen appeared to cyclometalate and coordinate with the metal center in an axial position.…”

“…In compound 2 the bond angle for C(21)−C(1)−C(11) (py−CO−py) is 106.49°. For this reason, many research groups have erroneously proposed that the metal-promoted hydration of the ketone in the dpk ligand is solely a result of steric strain on the carbonyl carbon, a desire of the carbonyl carbon to change from sp 2 hybridization to sp 3 hybridization to better accommodate the smaller bond agle. ,,,,,, An explanation for this behavior based on molecular models is that the bond strain and steric interaction within the system of the carbonyl carbon causes a transition from an sp 2 → sp 3 orbital hybridization upon ligation of the pyridyl rings. ,,,,,, In other words, the addition of the carbonyl spacer between the two pyridyl rings causes the chelation angle to be too large. As a result, the pyridyl rings fold up and pull in.…”

Influence of the Bridging Group of Cross-Conjugated Nitrogenous Bases on the Spectra and Structure of Solvatochromic Mixed-Ligand Copper(II) Chelates Containing β-Ketoenols

“…An sp 3 -hybridized carbon atom connecting the pyridyl groups and trans to the copper(II) ion accommodates 23 the adoption of the boat conformation by the chelate ring and facilitates the approach of the etheric oxygen to copper. These indicate that the resulting di(2-pyridyl)methoxymethanol acts as tridentate ligand as in Cu(dpC(OH)OCH 3 )Cl 2 …”

“…It is known that dpk (pyCOpy) upon chelation becomes susceptible to nucleophilic attack by protic molecules, 9 and, as recent investigations confirmed, the coordinated ketone reacts with alcohols to yield the corresponding semiacetals. 22 Thus the formulas [Cu(β)dpC(OH)OR]ClO 4 and [Cu(β)dpC(OH) 2 ]ClO 4 are more appropriate (Table 1). The predominant reaction of chelated 2,2′-dipyridylamine is deprotonation.…”

Copper(II)-Promoted Chemical Transformations of 3-Substituted 5-(2′-Pyridyl)-1,4-benzodiazepin-2-one Derivatives. Crystal Structures and Spectroscopic Characterisation of Metal Complexes

“…On the other hand coupled Cu−Cl and Cu−N bands could also be expected. The band at 364 cm −1 may be assigned to the ν(Cu−O) vibration, since it was found that ν(Cu−O) > ν(Cu−N) for this kind of metal complex 31,32. The situation is more complicated in complex 7 , where the internal deformation modes of the acetate ligand also falls into the same spectral region as the metal‐ligand vibrations.…”

Synthesis of Pt(dpk)Cl4 and the Reversible Hydration to Pt(dpk-O-OH)Cl3·H-phenCl: X-ray, Spectroscopic, and Electrochemical Characterization

“…In most cases where the metal:dpk ratio is 1:1, the ketone on the dpk ligand either does not hydrate at all or it remains a true gem -diol. One possible exception to this was reported with a copper(II) dpk compound in which the ketone had reacted with a methanol molecule in a fashion similar to hydration . In that case, the methoxy oxygen appeared to cyclometalate and coordinate with the metal center in an axial position.…”

“…In compound 2 the bond angle for C(21)−C(1)−C(11) (py−CO−py) is 106.49°. For this reason, many research groups have erroneously proposed that the metal-promoted hydration of the ketone in the dpk ligand is solely a result of steric strain on the carbonyl carbon, a desire of the carbonyl carbon to change from sp 2 hybridization to sp 3 hybridization to better accommodate the smaller bond agle. ,,,,,, An explanation for this behavior based on molecular models is that the bond strain and steric interaction within the system of the carbonyl carbon causes a transition from an sp 2 → sp 3 orbital hybridization upon ligation of the pyridyl rings. ,,,,,, In other words, the addition of the carbonyl spacer between the two pyridyl rings causes the chelation angle to be too large. As a result, the pyridyl rings fold up and pull in.…”