Inverse crown structures magnesium

E R. E. Mulvey, s-Block metal inverse crowns synthetic and structural synergism in mixed alkali metal-magnesium (or zinc) amide chemistry. Chem. Commun. 1049-56 (2001). 

Fig. 35 Molecular structure of sodium magnesium inverse crowns (A) [Na4Mg2(TMP)6(2,5-CgHsOMe)] 54, (B) [Na4Mg2 TMP)6(3,5-C6H3NMe2)] 55, and (C) [Na4Mg2(TMP)d3 5-CgHsMe)] 56.

Fig. 36 Molecular structure of sodium magnesium inverse crown [Na4Mg2(TMP)4 TTHP)2(1,4-CioH6)] 57.

The final part of this chapter will focus on the recent chemistry which has been reported involving potassium magnesiate chemistry. The first examples to be discussed involve the characterization of solvent-free potassium magnesiates which contain two TMP and one n-butyl anions per potassium (or magnesium) cation [ie, KMg(TMP)2 Bu ]. Three different oHgomeric forms have been reported including the polymeric [KMg(TMP)2 Bu]oo 62, the tetrameric [KMg(TMP)2 Bu]4 63, and the hexameric [KMg (TMP)2 Bu]6 64 examples (Fig. 41). The structures of 63 and 64 are architecturally similar to the inverse crowns discussed in Section 3.3 but they stiU retain the basic -butyl arm, and as such they have been coined as pre-inverse... 

Andrikopoulos PC, Armstrong DR, Kennedy AR, Mulvey RE, O Hara CT, Rowlings RJ3. Synthesis, structure and theoretical studies of the hydrido inverse crown [K2Mg2(N Pr2)4( a-H)2 (toluene)2] a rare example of a molecular magnesium hydride with a Mg-(p-H)2-Mg double bridge. EurJ Inorg Chem. 2003 2003(18) 3354-3362. 

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