Low-Coordinate Magnesium Sulfide and Selenide Complexes

• Published in: Inorganic chemistry 2023-10, Vol.62 (40), p.16443-16450
• Main Authors: Burnett, Stuart, Ferns, Rochelle, Cordes, David B., Slawin, Alexandra M. Z., van Mourik, Tanja, Stasch, Andreas
• Format: Article
• Language: English
• ISSN: 0020-1669; 1520-510X
• DOI: 10.1021/acs.inorgchem.3c02132

The reactions of [{(iPrDipNacNac)­Mg}2] 1 (iPrDipnacnac = HC­(iPrCNDip)2) with Ph3PO at 100 °C afforded the phosphinate complex [(iPrDipNacNac)­Mg­(OPPh3)­(OPPh2)] 3. Reactions of 1 with Ph3PE (E = S, Se) proceeded rapidly at room temperature to low-coordinate chalcogenide complexes [{(iPrDipNacNac)­Mg}2(μ-S)] 4 and [{(iPrDipNacNac)­Mg}2(μ-Se)] 5, respectively. Similarly, reactions of RNHCS ((MeCNR)2CS with R = Me, Et, or iPr) with 1 afforded NHC adducts of magnesium sulfide complexes, [{(iPrDipNacNac)­Mg­(RNHC)}­(μ-S)­{Mg­(iPrDipNacNac)}] 6, that could alternatively be obtained by adding the appropriate RNHC to sulfide complex 4. Complex 4 reacted with 1-adamantylazide (AdN3) to give [{(iPrDipNacNac)­Mg}2(μ-SN3Ad)] 7 and can form various simple donor adducts in solution, of which [(iPrDipNacNac)­Mg­(OAd)}2(μ-S)] 8a (OAd = 2-adamantanone) was structurally characterized. The nature of the ionic Mg–E–Mg unit is described by solution and solid-state studies of the complexes and by DFT computational investigations.