The Strange Case of Sodium (S)‑N‑α-(Methylbenzyl)allylamide: Anion Rearrangement, Decomposition, and a Peculiar Propyl Addition

An unexpected aza-enolate propyl addition complex, [(PhCCH2)­(CHC­(CH2CH2CH3)­CH3)­NNa·THF]∞ (1), was isolated when (S)-N-α-(methylbenzyl)­allylamine reacted in hexane with nBuNa in the presence of THF. Analytical studies revealed a decomposition of the sodium 1-azaallylamide to a sodium enamide and propene, identified by solution studies and a GC-headspace study, respectively. Propene then adds to the carbanion tautomer of the sodium 1-azaallylamide followed by anionic rearrangements to later form the aza-enolate propyl addition complex.