Mono- and dinuclear Pd(II) complexes of different salicylaldimine ligands as catalysts of transfer hydrogenation of nitrobenzene with cyclohexene and Suzuki–Miyaura coupling reactions

Silicon containing new salicylaldimine Pd(II) and Co(II) metal complexes as efficient catalysts in transformation of carbon dioxide (CO2) to cyclic carbonates

“…These signals are D 2 O exchangeable. This result indicates the involvement of the OH group in chelation with Pd(II) through displacement of ortho hydroxyl proton [28,29]. The singlets corresponding to azomethine group were observed between 8.60 and 8.42 ppm for ligands.…”

The orthopalladation dinuclear [Pd(L1)(μ-OAc)]2, [Pd(L2)(μ-OAc)]2 and mononuclear [Pd(L3)2] complexes with [N, C, O] or [N, O] containing ligands: Synthesis, spectral characterization, electrochemistry and catalytic properties

“…1). This result indicates that the (L 1 H) and (L 2 H) ligands bind palladium ions only through the imine nitrogen and aromatic carbon atoms, not through phenolic hydroxy groups [15,34]. Whereas, this characteristic band are not observed in the 1 H NMR spectra of [Pd(L 3 ) 2 ] complex, which indicates that the ligand (L 3 H) coordinates to palladium ion through imine nitrogen atom and the deprotonated phenolic hydroxy group.…”

“…The results indicate that introduction of different groups on in the salicylaldimine ring increases the catalytic activity of all complexes. The electron-donating/withdrawing and other functional groups probably increase the electron density on the Pd atom, which is subjected to electrophilic attack by a nitro group of nitrobenzene and double band of cyclohexene [13,34]. We carried out the same reaction under identical conditions without the catalyst, with organic ligand, with Pd(AcO) 2 .…”

Multinuclear Cu(II) Schiff Base Complex as Efficient Catalyst for the Chemical Coupling of CO2 and Epoxides: Synthesis, X-ray Structural Characterization and Catalytic Activity

“…The chemical shifts observed at d = 8.21 ppm for L 1 H, at d = 9.48 ppm for L 2 H and at d = 9.81 ppm for (L 3 H) is assigned to the proton of azomethine (CH=N) as singlet [28,29]. It is remarkable to see that the downfield chemical shift (d = 9.48 or 9.81 ppm) corresponds to the azomethine proton of the pyridine CH 3 group, which has the high electron donating power, while the upperfield value (d = 8.21 ppm) is of the allyl group with the high electron withdrawing power.…”