Spin crossover Fe(II) complexes of a cross-bridged cyclam derivative

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F18%3A73591080" target="_blank" >RIV/61989592:15310/18:73591080 - isvavai.cz</a>

Výsledek na webu

<a href="https://pubs.rsc.org/en/content/articlepdf/2018/dt/c8dt00414e" target="_blank" >https://pubs.rsc.org/en/content/articlepdf/2018/dt/c8dt00414e</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1039/c8dt00414e" target="_blank" >10.1039/c8dt00414e</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Spin crossover Fe(II) complexes of a cross-bridged cyclam derivative

Popis výsledku v původním jazyce

A cross-bridged cyclam derivative containing two 2-pyridylmethyl pendant arms (L = 4,11-bis((pyridin-2-yl)methyl)-1,4,8,11-tetraaza-bicyclo[6.6.2]hexadecane) was synthesized by dialkylation of the cross-bridged cyclam with 2-chloromethylpyridine. A series of Fe(ii) complexes with L and different counter anions of the formulas [Fe(L)][FeCl4 center dot H2O (1-H2O), [Fe(L)Cl-2.4H(2)O (2.4H(2)O), [Fe(L)](BF4)(2)center dot 0.5CH(3)CN (3.0.5CH(3)CN) and [Fe(L)](BPh4)(2)center dot CH3OH (4 center dot CH3OH) was prepared and thoroughly characterized. In all the cases, the [Fe(L)]2 cation adopts a cis-V configuration with a distorted octahedral geometry, and with the FeN6 donor set. The magnetic measurements within the temperature interval of 5-400 K revealed the spin crossover (SCO) behaviour of all the complexes with the transition temperature T-1/2 increasing with the counter anion in the order BF4- (3) &lt; [FeCl4](2-) (1) &lt; BPh4- (4). However, the SCO process was complete in the case of compound 3 only, with T1/2 = 177 K, which proceeded after removal of co-crystallized CH3CN molecules accompanied by a change of the crystallographic phase. The SCO behaviour of 3 was also confirmed by a single crystal X-ray analysis providing the average (Fe N)distances of 2.086 angstrom at 120 K and 2.197 angstrom at 293 K typical of low-spin, and high-spin Fe-II complexes, respectively. The obtained results clearly showed that the nature of the counter anion and the presence/absence of co-crystallized solvent molecule(s) significantly affected the temperature as well as the abruptness of the spin transition. This is the first report of SCO behaviour observed for iron complexes containing a cross-bridged cyclam derivative.

Název v anglickém jazyce

Spin crossover Fe(II) complexes of a cross-bridged cyclam derivative

Popis výsledku anglicky

A cross-bridged cyclam derivative containing two 2-pyridylmethyl pendant arms (L = 4,11-bis((pyridin-2-yl)methyl)-1,4,8,11-tetraaza-bicyclo[6.6.2]hexadecane) was synthesized by dialkylation of the cross-bridged cyclam with 2-chloromethylpyridine. A series of Fe(ii) complexes with L and different counter anions of the formulas [Fe(L)][FeCl4 center dot H2O (1-H2O), [Fe(L)Cl-2.4H(2)O (2.4H(2)O), [Fe(L)](BF4)(2)center dot 0.5CH(3)CN (3.0.5CH(3)CN) and [Fe(L)](BPh4)(2)center dot CH3OH (4 center dot CH3OH) was prepared and thoroughly characterized. In all the cases, the [Fe(L)]2 cation adopts a cis-V configuration with a distorted octahedral geometry, and with the FeN6 donor set. The magnetic measurements within the temperature interval of 5-400 K revealed the spin crossover (SCO) behaviour of all the complexes with the transition temperature T-1/2 increasing with the counter anion in the order BF4- (3) &lt; [FeCl4](2-) (1) &lt; BPh4- (4). However, the SCO process was complete in the case of compound 3 only, with T1/2 = 177 K, which proceeded after removal of co-crystallized CH3CN molecules accompanied by a change of the crystallographic phase. The SCO behaviour of 3 was also confirmed by a single crystal X-ray analysis providing the average (Fe N)distances of 2.086 angstrom at 120 K and 2.197 angstrom at 293 K typical of low-spin, and high-spin Fe-II complexes, respectively. The obtained results clearly showed that the nature of the counter anion and the presence/absence of co-crystallized solvent molecule(s) significantly affected the temperature as well as the abruptness of the spin transition. This is the first report of SCO behaviour observed for iron complexes containing a cross-bridged cyclam derivative.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10402 - Inorganic and nuclear chemistry

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

DALTON TRANSACTIONS

ISSN

1477-9226

e-ISSN

—

Svazek periodika

47

Číslo periodika v rámci svazku

17

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

12

Strana od-do

6134-6145

Kód UT WoS článku

000431816000031

EID výsledku v databázi Scopus

2-s2.0-85046291871