Chiral 1,8-naphthyridine based ligands: Syntheses and characterization of Di- and tetranuclear copper (I) and silver (I) complexes

Cuprophilic Interactions in and between Molecular Entities

“…In addition, the 1,8-naphthyridine backbonew ith one oxazoline (OX) group was used to assemble the cationic dicopper complex[ Cu 2 (m-I)(m-k 2 :k 1 -NAPY-OX) 2 ](OTf) (18)( Figure 1). [158] Unlike 16 and 17,t wo Cu atoms were spanned by two tridentate naphthyridine ligands and one iodine atom, and as such the two Cu atoms displayadistorted tetrahedral geometry.A lthougha ll Cu atomsa re tetra-coordinate in 16-18, 18 was found to have the longest Cu-Cu distance of 2.6189(9) ,a ttributable to the larger iodido ligand.…”

“…2019, 25,8936 -8954 www.chemeurj.org CP)] (17)w ere synthesized for testing their catalytic activity in organic transformations( see below). [157,158] Both 16 and 17 were essentially isostrctural with two Cu atoms being bridged by one tetradentate1 ,8-naphthyridine, and both featured a butterfly-shaped Cu 2 (m-Cl) 2 unit. The Cu-Cu distances in 16 and 17 were 2.558(2) and 2.6432(11) ,r espectively,l onger than those of 1-15,e xcluding 11,p resumably due to each copperc enter with ah igherc oordinationn umber of four.…”

“…As reported by Bera et al., two dicopper(I) complexes supported by either 1,8‐naphthyridine‐based ligands with two mesitylimine (MI) groups [Cu 2 (μ‐Cl) 2 (μ‐κ 2 :κ 2 ‐NAPY‐MI)] ( 16 ) or two camphor‐pyrazole (CP) substituents [Cu 2 (μ‐Cl) 2 (μ‐κ 2 :κ 2 ‐NAPY‐CP)] ( 17 ) were synthesized for testing their catalytic activity in organic transformations (see below) . Both 16 and 17 were essentially isostrctural with two Cu atoms being bridged by one tetradentate 1,8‐naphthyridine, and both featured a butterfly‐shaped Cu 2 (μ‐Cl) 2 unit.…”

“…Complex 17 was demonstrated as an efficient catalyst for a variety of reactions, such as cyclopropanation of styrene, N−H insertion of aniline with diazoacetates, and nitroaldol reactions. In addition, the 1,8‐naphthyridine backbone with one oxazoline (OX) group was used to assemble the cationic dicopper complex [Cu 2 (μ‐I)(μ‐κ 2 :κ 1 ‐NAPY‐OX) 2 ](OTf) ( 18 ) (Figure ) . Unlike 16 and 17 , two Cu atoms were spanned by two tridentate naphthyridine ligands and one iodine atom, and as such the two Cu atoms display a distorted tetrahedral geometry.…”

Synthesis of unsymmetrical 1,8-naphthyridine-based ligands for the assembly of tri-and tetra-nuclear copper(ii) complexes

“…2,3 As part of these efforts during the last years, the significance of 2,7-disubstituted 1,8naphthyridine based ligands displays a growing importance in the field of organometallic/coordination chemistry. The 1,8naphthyridine core is able to stabilize two metal ions in close proximity such as nickel(II), 4,5 cobalt, 6 ruthenium, 7,8,9 or copper(I) 10,11,12 and (II) 4,13 . The corresponding intramolecular electronic interactions between the metal centers are strongly influenced by the short metal-metal distances, impacting the corresponding redox, magnetic, spectroscopic and reactivity properties.…”