Unexpected Formation of Tris(tert-butyl)-4a,8a,12a- trihydroxydecahydro-2,6,10-triazatriphenylene-2,6,10- triscarboxylate via the Reaction of tert-Butylpiperidin- 4-one-l-carboxylate with Sodium Bis(trimethylsilyl)amide

摘要

The piperidine derivatives are of interest as biologically active compounds with a diverse range of activity [1, 2]. One of the key substrates to prepare such derivatives is the commercially available tert-butylpiperidin-4-one-l-carboxylate I. In this work we first tried to perform the metallation of ketone I with sodium bis(trimethylsilyl)amide II solution in order to functionalize the resulting sodium salt III by treating with a variety of the electrophilic reagents. However, in the case of the reaction between reagents I and II the usual [3] treatment of the reaction mixture yields new substance IV (along with the unreacted ketone I) whose structure was established by the elemental analysis, IR, ~1H NMR spectroscopy, and GC-MS method. The formation of this compound is likely to occur as a result of the regioselective intermolecular interaction of three molecules of the ambidentate sodium anion III.