Reductive Isopropyl Radical Elimination from (dpp-bian)Mg-iPr(Et2O)

The reaction of (dpp-bian)Na(Et2O) with one equiv. of iPrMgCl in hexane affords (dpp-bian)Mg-iPr(Et2O) (1) whereas (dpp-bian)Mg(Et2O)2 (2) is formed when this reaction is carried out in Et2O as a result of isopropyl radical elimination. Compound 1 which is stable in hexane and Et2O also decomposes in THF with elimination of isopropyl radicals yielding (dpp-bian)Mg(THF)2. The reaction of (dpp-bian)Na2(Et2O)3 with two equiv. of iPrMgCl in Et2O produces 2 and iPr2Mg, which then interact to give (dpp-bian)(Mg-iPr)2(Et2O) (3) when treated with hexane or toluene. Compounds 1–3 were characterized by elemental analysis, UV/Vis and NMR spectroscopy, as well as by single-crystal X-ray diffraction. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

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