An organometallic fragment that is receiving increasing attention within synthetic chemists is the {6-arene ruthenium}2+ which can be complexed with a wide number of mono-, bi- or tridentate ligands thus affording half-sandwich complexes, that have found several synthetic applications. The -ligated arene confers great stability to Ru in +2 oxidation state, and the characteristic “piano stool” structure offers the possibility to vary the additional donors via substitution of halide(s) with a variety of -donors ranging from phosphines [1] to -diketones [2], to aliphatic as well as aromatic amines [3]. Among the latter ones, we have contributed by studies on the coordination chemistry of bis(pyrazolyl)alkanes [4] and bis(pyrazolyl)acetates [5]. Here we report preliminary data on the reactivity of some arene ruthenium fragments (arene = benzene, para-cymene or hexamethyl benzene) with a new class of heteroscorpionate ligands, namely the tris(pyrazolyl)methanesulfonates, containing three pyrazole rings and a SO3 group on the briging carbon atom. Their interaction with the dinuclear metal precursors [(arene)RuCl2]2 in methanol readily afforded novel ionic derivatives containing 3-ligands as in scheme 2. However, by using the more crowded TpmsPh donor only the benzene derivative has been obtained in the same reaction conditions (scheme 2). Their structure has been confirmed by analytical and spectral (IR, 1H, 13C, ESI-MS) data and also by X-ray diffraction studies (Fig. 1).
Reactivity of novel heteroscorpionates with arene ruthenium(II) fragments
MARCHETTI, Fabio;PETTINARI, Claudio;DI NICOLA, CORRADO;
2009-01-01
Abstract
An organometallic fragment that is receiving increasing attention within synthetic chemists is the {6-arene ruthenium}2+ which can be complexed with a wide number of mono-, bi- or tridentate ligands thus affording half-sandwich complexes, that have found several synthetic applications. The -ligated arene confers great stability to Ru in +2 oxidation state, and the characteristic “piano stool” structure offers the possibility to vary the additional donors via substitution of halide(s) with a variety of -donors ranging from phosphines [1] to -diketones [2], to aliphatic as well as aromatic amines [3]. Among the latter ones, we have contributed by studies on the coordination chemistry of bis(pyrazolyl)alkanes [4] and bis(pyrazolyl)acetates [5]. Here we report preliminary data on the reactivity of some arene ruthenium fragments (arene = benzene, para-cymene or hexamethyl benzene) with a new class of heteroscorpionate ligands, namely the tris(pyrazolyl)methanesulfonates, containing three pyrazole rings and a SO3 group on the briging carbon atom. Their interaction with the dinuclear metal precursors [(arene)RuCl2]2 in methanol readily afforded novel ionic derivatives containing 3-ligands as in scheme 2. However, by using the more crowded TpmsPh donor only the benzene derivative has been obtained in the same reaction conditions (scheme 2). Their structure has been confirmed by analytical and spectral (IR, 1H, 13C, ESI-MS) data and also by X-ray diffraction studies (Fig. 1).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
