The crystal and molecular structure of potassium aquapentachloroiridate(III) and the 1H, 13C, 15N NMR coordination shifts in iridium(III) chloride complexes with 2,2′-bipyridine or 1,10-phenanthroline

15N NMR coordination shifts in Pd(II), Pt(II), Au(III), Co(III), Rh(III), Ir(III), Pd(IV), and Pt(IV) complexes with pyridine, 2,2′-bipyridine, 1,10-phenanthroline, quinoline, isoquinoline, 2,2′-biquinoline, 2,2′:6′, 2′-terpyridine and their alkyl or aryl

“…[34] The differences between their values for nitrogens trans to N (ca 111-117 ppm for both cis-[Ir(LL) 2 2 Cl 2 ] + ) [34] are ca 20-30 ppm larger than in case of their Rh(III) analogs. The trans influence of H is ca 40-50 ppm weaker, as for a triphenylphosphine-hydride-chloride complex with py, [33] ; nevertheless, it is ca 20 ppm more than that for the respective Rh (III) analog, trans(H,N)…”

“…The significance of the trans effect is also illustrated by the set of rhodoximes containing axial py and various auxiliary ligands X, described by Rentsch et 2 ] formula (P * = triphenylphosphine, P(C 6 H 5 ) 3 ; tribenzylphosphine, P(CH 2 C 6 H 5 ) 3 ; tricyclohexylphosphine, P(C 6 H 11 ) 3 ), for which the | 15N coord | parameters are ca 48-56 ppm [26] ; in case of another trans (H,N) [33,34] (Table 6 2 Cl 2 ] + , the | 15N coord | parameters vary within ca 106-120 ppm range. [34] The differences between their values for nitrogens trans to N (ca 111-117 ppm for both cis-[Ir(LL) 2 2 Cl 2 ] + ) [34] are ca 20-30 ppm larger than in case of their Rh(III) analogs.…”

“…However, the full set of 15 . [7,20,34] Moreover, all these species were measured in the same DMSO-d 6 medium, except for [Ir(bpy) Cl 4 ] − (in D 2 O), and at the same temperature of 303 K. [7,20,34] Generally, it is evident that each | 15N coord | parameter is usually ca 5-10 ppm larger for the phen than the bpy chloride complex with the same metal (95. 3 [34] ), which may be caused by the change of solvent (DMSO-d 6 vs D 2 O).…”

Solvent Effects on Nitrogen Chemical Shifts

“…The shielding effects for Ir(III) complexes are significantly larger than those of the analogous Co(III) and Rh(III) complexes (Tables 5 and 6) [84]. Thus, [Ir(LL)Cl 4 ] À complexes have jΔ 15N coord j of $106-117 ppm, whereas cis-[Ir(LL) 2 Cl 2 ] + $115-118 ppm [91]. In analogy to the corresponding cis-[Co(LL) 2 Cl 2 ] + , the shielding of a nitrogen trans to chlorine is larger (3-8 ppm) than of that trans to a nitrogen.…”

“…Typical δ 15N and Δ 15N coord for the selected transition metals, taking in to account their oxidation state, the N-donor ligand(s), and the coordinating atom trans to the nitrogen donor, are shown. The magnitudes of jΔ 15N coord j of these azine-transition metal complexes vary within a considerably broad range, $30 to $150 ppm [59,60,65,66,90,91].…”