Structures of Organomagnesium Compounds in the Solid State

Relevant Bond Angles and Bond Lengths for Type 5 Compounds 

Some years after the presentation of the monomeric structure of ethyl-magnesium bromide, a centrosymmetric dimer of the same compound was reported (6a) (20). In this complex, which has the composition (ethylmag- 

During our own investigations, we obtained crystal structures of the tetrahydrofuranate complexes of diphenylmagnesium and bis(p-toIyI)mag-nesium. The publication of these structures is in preparation (22a). The first compound (51) crystallized as the expected monomeric bis(tetrahydrofuranate) in analogy to 5f. Some characteristic structural parameters of 51 

In the absence of coordinating solvents like ethers, most organomagnesium compounds tend to form polymeric structures. Microcrystalline solids or viscous liquids are generally obtained on desolvation of organomagnesium ether complexes, which are almost insoluble in apolar (non- 

The use of powder diffraction for structure determination is limited to simple molecules, since for the resolution of larger molecules too many structural assumptions have to be made. In those cases, it will be necessary to obtain single crystals. Until recently, however, no examples were known in the literature, undoubtedly owing to experimental difficulties. In principle, three approaches for obtaining good quality crystals are available  

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