Synthesis and Crystal Structure of [{nBuMg(-TMP)}2] and of a Homometallic Inverse Crown in Tetranuclear [{nBuMg_2[μ-N(H)Dipp]_2(μ_3-OnBu)}_2]

摘要

Although the first substantial studies of organomagnesium amides "RMgN(R~1)(R~2)" took place in the 1960s through the pioneering work of Coates et al., their impact on synthesis since then has been almost invisible in comparison to that of Grignard reagents or lithium organoamides. However, recent communications by Eaton and co-workers thrusting "BuMgNiPr_2" into the limelight as a new Bronsted base for regioselective deprotonation of cyclopropane and cyclobutane carboxamides could mark a watershed in the appreciation and utilization of these hitherto largely friendless organometallics. "BuMgNiPr_2" is now sold commercially in the form of a THF solution by the chemical company Aldrich, but not as a single, well-defined compound as it contains a mixture of n-butyl and sec-butyl components.