Transition Metal Coordination Chemistry ofN,N-Bis(2-{pyrid-2-ylethyl})hydroxylamine

Abstract

Although directly relevant to metal mediated biological nitrification as well as the coordination chemistry of peroxide, the metal complexes of hydroxylamines and their functionalized variants remain largely unexplored. The chelating hydroxylamine ligand N,N-bis(2-{pyrid-2-ylethyl})hydroxylamine can be readily generated via a solvent free reaction in high purity; however, the ligand is prone to decomposition which can hamper metal reaction. N,N-bis(2-{pyrid-2-ylethyl})hydroxylamine forms stable complexes with chromium(III), manganese(II), nickel(II), and cadmium(II) ions, coordinating in a side-on mode in the case of chromium and via the nitrogen in the case of the latter three metal ions. The hydroxylamine ligand can also be reduced to form N,N-bis(2-{pyrid-2-ylethyl})amine upon exposure to a stoichiometric amount of the metal salts cobalt(II) nitrate, vanadium(III) chloride, and iron(II) chloride. In the reaction with cobalt nitrate, the reduced ligand then chelates to the metal to form [N,N-bis(2-{pyrid-2-ylethyl})amine]dinitrocobalt(II). Upon reaction with vanadium(III) chloride and iron(III) chloride, the reduced ligand is isolated as the protonated free base, resulting from a metal-mediated decomposition reaction.

AlMe3, GaMe3 and InMe3 Adducts of N,N‐Bis(2‐{pyrid‐2‐yl}ethyl)hydroxylaminato Rare‐Earth Metal Complexes and Their Molecular Dynamics

“…[22] This coordination mode in 6-12 leads to two six-membered Ln-N-C-C-C-N rings adopting a strongly distorted boat conformation.…”

Hydroxylamine-O-sulfonamide is a versatile lead compound for the development of carbonic anhydrase inhibitors

“…these maps, although being very well defined for the protein residues, did not allow discriminating unambiguously the inhibitor binding mode. Indeed, two different models were compatible with electron density maps: the first one with the catalytic zinc ion coordinated by the sulfonamide nitrogen (hereafter indicated as binding mode A) and the second one where the coordination was due to the hydroxylamine moiety in a side-on (Z 2 ) fashion 11 (hereafter indicated as binding mode B) (Fig. 2).…”

Interaction of Chromium(III) with a N,N′-Disubstituted Hydroxylamine-(diamido) Ligand: A Combined Experimental and Theoretical Study

“…The possibility of formation of the neutral compound cis -[Cr III (hydia)Cl 2 ] ( 3 ) in solution (Scheme ) with a structure similar to the previously reported Cr(III) complex with the N , N ′-disubstituted hydroxylamine ligand Hbipyh, cis -[Cr III (bipyh)Cl 2 ] ( 4) , (Scheme ), was also examined. For compound 3 , a peak at ∼580 nm is predicted for the 4 A 2 ← 4 T 2 transition, assuming O h symmetry d–d transition (however, the structure of complexes 3 and 4 exhibit approximately a C 2 v symmetry, and thus, the peak at 580 nm will be due to 4 A 2 + 4 B 1 + 4 B 2 ← 4 A 2 transitions), using the UV–vis experimental data of 4 and the Jorgensen’s equation to calculate the difference of the contribution of the two amide oxygen atoms versus the pyridine nitrogen atoms.…”