Pendant arm N-monofunctionalised 1,4,7-triazacyclononane complexes of Fe(ii) and Ru(ii)

Abstract

A series of triazacyclononane and pendant arm triazacyclononane derivatives of iron() and ruthenium() have been investigated. The objective of this work was (i) to stabilise reactive Fe() dichloride fragments using N-monofunctionalised 1,4,7-triazacyclononane macrocycles and (ii) to investigate the effect of pendant group macrocycles in order to create different Ru() environments. DALTON

Carbonyl[1-(2-pyridylmethyl)-1,4,7-triazacyclononane-κ4N](triphenylphosphine)ruthenium(II) dichloride dichloromethane sesquisolvate

“…The fourth RuÐN bond, Ru1ÐN12 in this particular structure, is 2.120 (3) A Ê . This is in contrast with the ®rst reported structure of this type, in which the pyridyl RuÐN bond of the pendant arm ligand is shorter than the RuÐN bonds involving the macrocycle (Gott et al, 2002). As expected, the longest RuÐN bond (Ru1ÐN4) lies trans to the carbonyl ligand.…”

“…The angle between the N atom of the macrocyclic ring and the N atom of the pendant pyridine arm donor [N1ÐRu1ÐN12 = 79.20 (12) ] is slightly smaller due to the more strained nature of the interaction of the pendant arm with the ruthenium centre. The three RuÐN bond distances [Ru1ÐN1 = 2.136 (3) A Ê , Ru1ÐN4 = 2.167 (3) A Ê and Ru1ÐN7 = 2.113 (3) A Ê ] are in agreement with expected values for general complexes of this type (Gott et al, 2002(Gott et al, , 2003; however, in the quoted reference, the values are more similar than in this instance. The fourth RuÐN bond, Ru1ÐN12 in this particular structure, is 2.120 (3) A Ê .…”

“…We have recently published the ®rst studies of N-monofunctionalized 1,4,7-triazacyclononane complexes of ruthenium (Gott et al, 2002(Gott et al, , 2003. We have also investigated the reaction of such ligands with compounds of the general type RuHClL 4 (Gott & McGowan, 2003).…”

1,4,7-Tris(p-toluenesulfonyl)-1,4,7-triazacyclononane

“…The importance of (I) is shown in the wide use of the parent macrocycle, 1,4,7-triazacyclononane, and derived ligands in both coordination chemistry (Chaudhuri & Wieghardt, 1987) and organometallic chemistry (e.g. Male et al, 2000;Bambirra et al, 2001;Gott et al, 2002;Cui et al, 2003). Part of the widespread synthetic utility of (I) is the ability to introduce, by selective detosylation, further functional groups at one, two, or all three N atoms, thus giving a wide and varied range of multidentate ligands (Wainwright, 1997).…”

Spin Cross-Over (SCO) Complex Based on Unsymmetrical Functionalized Triazacyclononane Ligand: Structural Characterization and Magnetic Properties

“…In order to further investigate the effect of the size of the macrocycle ring of such hexadentate ligands on the coordination properties and ligand field, several Fe(II) systems that are based on triazamacrocycle units involving pyridylmethyl, aniline, methylimidazol, methylpyrazol or methylthiophene groups have been reported [50][51][52][53][54][55][56][57][58][59]. However, to the best of our knowledge, only two systems have been described as SCO systems in the solid state [50,51].…”