Cyclopropylmagnesium scorpionates: A missing member of the series with both staggered and eclipsed rotamers in the crystal

Quentin Dufrois (1, 2) , Sonia Mallet-Ladeira (3, 1) , Chiara Dinoi (1, 2) , Michel Etienne (1, 2)

1 LCC - Laboratoire de chimie de coordination
2 UT3 - Université Toulouse III - Paul Sabatier
3 ICT - Institut de Chimie de Toulouse

The reaction of the hydrotris(3,5-dimethylpyrazolyl)borate potassium salt KTpMe2 with [Mg(c-C3H5)2(dioxane)x] gives [TpMe2Mg(c-C3H5)] (1) in 70 % yield. Full characterization includes an X-ray diffraction study, which reveals the presence of both staggered and eclipsed rotamers around the Mg–C bond of 1 in the unit cell. There is no evidence for any agostic interaction. Complex 1 does not undergo the Schlenk equilibrium. The complex [(F12-Tp4Bo,3Ph)Mg(c-C3H5)] (2) containing a hydrotris(tetrafluoro-3-phenylindazolyl)borate scorpionate ligand, is obtained in 20 % yield. Complex 2 proved to be significantly more labile than 1, solutions of 2 giving readily [Mg(F12-Tp4Bo,3Ph)2] (3). This study emphasizes the importance of tuning the steric and electronic properties of the scorpionate ligands for the stabilization of heteroleptic magnesium alkyl complexes.

Domaines: Chimie de coordination

Quentin Dufrois, Sonia Mallet-Ladeira, Chiara Dinoi, Michel Etienne. Cyclopropylmagnesium scorpionates: A missing member of the series with both staggered and eclipsed rotamers in the crystal. European Journal of Inorganic Chemistry, 2018, 20-21, pp.2387-2392. ⟨10.1002/ejic.201800073⟩. ⟨hal-01953090⟩