Secondary amides, organomagnesium amide

FIGURE 100. Schematic representation of the stmctures of organomagnesium amides 255-263 derived from secondary amines... 

A simple synthetic route to compounds of the type R Mg(NR R ) is the reaction of equimolar amounts of MgR and a secondary amine, HNR R . By this method sterically hindered 1,3,6,8-tetra-t-butylcarbazole and diethylmagnesium in THF afford 52 as the bistetrahydrofuran adduct, and hexamethyldisilazane (HN(TMS)2) and "BuMg Bu in heptane form nonsolvated 53 [23]. Metalation of activated G-H groups by the amide bases Mg(TMP)2 (TMPH = 2,2,6,6-tetramethylpiperidine) or Mg(N Pr2)2 can also produce organomagnesium amides. Reactions of metal amide (MNR R (M = Li or Na)) with the appropriate Grignard reagent have been used to produce 54 [24] and 55 [25] (Scheme 3.31). 

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