Versatility of Coordination Modes in Complexes of Monohydroxamic Acids with Half-Sandwich Type Ruthenium, Rhodium, Osmium and Iridium Cations

P. Buglyó, Péter L. Parajdi-Losonczi, A. Bényei, Norbert Lihi, Linda Bíró, E. Farkas

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Complexation of the secondary N-methyl-acetohydroxamic acid (HMeaha) with [(η6-p-cym)Ru(H2O)3]2+, [(η5-Cp*)Rh(H2O)3]2+, [(η6-p-cym)Os(H2O)3]2+ or [(η5-Cp*)Ir(H2O)3]2+ cations and the primary acetohydroxamic acid (HAha) with the former two cations (first time in the literature) has been studied in aqueous solution using pH-potentiometry, NMR, ESI-MS and DFT calculations. Because the arene or arenyl ligands take three coordination sites of the metal ion, only three remain free for interaction with additional ligand(s). Meaha forms five-membered hydroxamate type chelated [ML]+ and [M(OH)L], being the third coordination site occupied by a water molecule in the former complex and by a hydroxide ion in the latter one. While [ML]+ remains predominant even under basic conditions in the Ru- and Rh-containing systems, it is measurable only in slightly acidic region with the two 5d metal ions. Also the tendency for hydrolysis of the aqua ligand in [ML(H2O)]+ complexes follows the trend of the cations for hydrolysis, Os > Ir > Ru > Rh. The X-ray result did not show any role of the H substituent of Aha in [{(η5-Cp*)Rh}22-Aha)2]2+, in solution, however, its significant role was supported especially with Ru. All the results support the formation of a stable trinuclear [M3H–2L3(H2O)]+ species in which doubly deprotonated (hydroxymate type) ligands bridge two metal centres by coordinating via the two oxygens to the one cation and via the N-donor to another one.

Original languageEnglish
Pages (from-to)8127-8136
Number of pages10
JournalChemistrySelect
Volume2
Issue number26
DOIs
Publication statusPublished - Jan 1 2017

Fingerprint

Osmium
Iridium
Rhodium
Ruthenium
Cations
Ligands
Acids
Metal ions
Hydrolysis
Complexation
Discrete Fourier transforms
Metals
Nuclear magnetic resonance
Oxygen
X rays
Molecules
Water

Keywords

  • Anticancer
  • Half-sandwich platinum metals
  • Hydroxamic acid
  • Speciation

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

Versatility of Coordination Modes in Complexes of Monohydroxamic Acids with Half-Sandwich Type Ruthenium, Rhodium, Osmium and Iridium Cations. / Buglyó, P.; Parajdi-Losonczi, Péter L.; Bényei, A.; Lihi, Norbert; Bíró, Linda; Farkas, E.

In: ChemistrySelect, Vol. 2, No. 26, 01.01.2017, p. 8127-8136.

Research output: Contribution to journalArticle

@article{031e58f88acc4d2aae21769b56b71e47,
title = "Versatility of Coordination Modes in Complexes of Monohydroxamic Acids with Half-Sandwich Type Ruthenium, Rhodium, Osmium and Iridium Cations",
abstract = "Complexation of the secondary N-methyl-acetohydroxamic acid (HMeaha) with [(η6-p-cym)Ru(H2O)3]2+, [(η5-Cp*)Rh(H2O)3]2+, [(η6-p-cym)Os(H2O)3]2+ or [(η5-Cp*)Ir(H2O)3]2+ cations and the primary acetohydroxamic acid (HAha) with the former two cations (first time in the literature) has been studied in aqueous solution using pH-potentiometry, NMR, ESI-MS and DFT calculations. Because the arene or arenyl ligands take three coordination sites of the metal ion, only three remain free for interaction with additional ligand(s). Meaha– forms five-membered hydroxamate type chelated [ML]+ and [M(OH)L], being the third coordination site occupied by a water molecule in the former complex and by a hydroxide ion in the latter one. While [ML]+ remains predominant even under basic conditions in the Ru- and Rh-containing systems, it is measurable only in slightly acidic region with the two 5d metal ions. Also the tendency for hydrolysis of the aqua ligand in [ML(H2O)]+ complexes follows the trend of the cations for hydrolysis, Os > Ir > Ru > Rh. The X-ray result did not show any role of the H substituent of Aha– in [{(η5-Cp*)Rh}2(μ2-Aha)2]2+, in solution, however, its significant role was supported especially with Ru. All the results support the formation of a stable trinuclear [M3H–2L3(H2O)]+ species in which doubly deprotonated (hydroxymate type) ligands bridge two metal centres by coordinating via the two oxygens to the one cation and via the N-donor to another one.",
keywords = "Anticancer, Half-sandwich platinum metals, Hydroxamic acid, Speciation",
author = "P. Bugly{\'o} and Parajdi-Losonczi, {P{\'e}ter L.} and A. B{\'e}nyei and Norbert Lihi and Linda B{\'i}r{\'o} and E. Farkas",
year = "2017",
month = "1",
day = "1",
doi = "10.1002/slct.201701858",
language = "English",
volume = "2",
pages = "8127--8136",
journal = "ChemistrySelect",
issn = "2365-6549",
publisher = "Wiley-Blackwell Publishing Ltd",
number = "26",

}

TY - JOUR

T1 - Versatility of Coordination Modes in Complexes of Monohydroxamic Acids with Half-Sandwich Type Ruthenium, Rhodium, Osmium and Iridium Cations

AU - Buglyó, P.

AU - Parajdi-Losonczi, Péter L.

AU - Bényei, A.

AU - Lihi, Norbert

AU - Bíró, Linda

AU - Farkas, E.

PY - 2017/1/1

Y1 - 2017/1/1

N2 - Complexation of the secondary N-methyl-acetohydroxamic acid (HMeaha) with [(η6-p-cym)Ru(H2O)3]2+, [(η5-Cp*)Rh(H2O)3]2+, [(η6-p-cym)Os(H2O)3]2+ or [(η5-Cp*)Ir(H2O)3]2+ cations and the primary acetohydroxamic acid (HAha) with the former two cations (first time in the literature) has been studied in aqueous solution using pH-potentiometry, NMR, ESI-MS and DFT calculations. Because the arene or arenyl ligands take three coordination sites of the metal ion, only three remain free for interaction with additional ligand(s). Meaha– forms five-membered hydroxamate type chelated [ML]+ and [M(OH)L], being the third coordination site occupied by a water molecule in the former complex and by a hydroxide ion in the latter one. While [ML]+ remains predominant even under basic conditions in the Ru- and Rh-containing systems, it is measurable only in slightly acidic region with the two 5d metal ions. Also the tendency for hydrolysis of the aqua ligand in [ML(H2O)]+ complexes follows the trend of the cations for hydrolysis, Os > Ir > Ru > Rh. The X-ray result did not show any role of the H substituent of Aha– in [{(η5-Cp*)Rh}2(μ2-Aha)2]2+, in solution, however, its significant role was supported especially with Ru. All the results support the formation of a stable trinuclear [M3H–2L3(H2O)]+ species in which doubly deprotonated (hydroxymate type) ligands bridge two metal centres by coordinating via the two oxygens to the one cation and via the N-donor to another one.

AB - Complexation of the secondary N-methyl-acetohydroxamic acid (HMeaha) with [(η6-p-cym)Ru(H2O)3]2+, [(η5-Cp*)Rh(H2O)3]2+, [(η6-p-cym)Os(H2O)3]2+ or [(η5-Cp*)Ir(H2O)3]2+ cations and the primary acetohydroxamic acid (HAha) with the former two cations (first time in the literature) has been studied in aqueous solution using pH-potentiometry, NMR, ESI-MS and DFT calculations. Because the arene or arenyl ligands take three coordination sites of the metal ion, only three remain free for interaction with additional ligand(s). Meaha– forms five-membered hydroxamate type chelated [ML]+ and [M(OH)L], being the third coordination site occupied by a water molecule in the former complex and by a hydroxide ion in the latter one. While [ML]+ remains predominant even under basic conditions in the Ru- and Rh-containing systems, it is measurable only in slightly acidic region with the two 5d metal ions. Also the tendency for hydrolysis of the aqua ligand in [ML(H2O)]+ complexes follows the trend of the cations for hydrolysis, Os > Ir > Ru > Rh. The X-ray result did not show any role of the H substituent of Aha– in [{(η5-Cp*)Rh}2(μ2-Aha)2]2+, in solution, however, its significant role was supported especially with Ru. All the results support the formation of a stable trinuclear [M3H–2L3(H2O)]+ species in which doubly deprotonated (hydroxymate type) ligands bridge two metal centres by coordinating via the two oxygens to the one cation and via the N-donor to another one.

KW - Anticancer

KW - Half-sandwich platinum metals

KW - Hydroxamic acid

KW - Speciation

UR - http://www.scopus.com/inward/record.url?scp=85041724649&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85041724649&partnerID=8YFLogxK

U2 - 10.1002/slct.201701858

DO - 10.1002/slct.201701858

M3 - Article

AN - SCOPUS:85041724649

VL - 2

SP - 8127

EP - 8136

JO - ChemistrySelect

JF - ChemistrySelect

SN - 2365-6549

IS - 26

ER -