T.Kruczynski, N.Pushkarevsky, P. Henke, R. Kоppe, E. Baum,
S. Konchenko, J. Pikies, H. Schnоckel "Hunting for the Magnesium(I) Species: Formation, Structure, and
Reactivity of some Donor-Free Grignard Compounds" // Angew. Chem. Int. Ed. 2012, 51, 9025–9029.
http://onlinelibrary.wiley.com/doi/10.1002/anie.201206128/abstract