An unprecedented Pd-catalyzed cascade Wacker-Heck lactonization-cyclization sequence is reported. The process provides a facile approach to bi- and tricyclic spiranoid lactones in good yields. The reaction shows general substrate scope and a broad functional group tolerability. In addition, a rare 4-exo trig Heck-type cyclization is demonstrated.

The new reactivity of α,β-unsaturated enaminones driven by their "dual electronic attitude" is reported. We introduce unexplored, α-enaminone synthones and reveal the unusual functionalities of these building blocks. The feasibility of this new concept is demonstrated in the direct functionalization of enaminone precursors, such as alkylation; 1,2- 1,3-, or 1,4-addition; and C-O bond formation. The general and potential applicability is presented through the collective synthesis of several important classes of heterocycles via controlled cyclizations of easily accessible common precursors. The rapid composition of novel key α-enaminone synthones yields an assembly of oxazines, azaspirones, quinolinones, and quinolinols in a regio- and chemoselective fashion.

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Cascade Pd(II)-Catalyzed Wacker Lactonization-Heck Reaction: Rapid Assembly of Spiranoid Lactones. -The new unprecedented Wacker-Heck lactonization--cyclization reaction provides bi-and tricyclic spiranoid lactones in good yields. The reaction shows general substrate scope and a broad functional group tolerability. In addition, a rare 4-exo trig Heck-type cyclization is demonstrated. -(ALBARGHOUTI, G.; KOTIKALAPUDI, R.; LANKRI, D.; VALERIO, V.; TSVELIKHOVSKY*, D.; Chem. Commun. (Cambridge) 52 (2016) 15, 3095-3098, http://dx.doi.org/10.1039/C5CC09923D ; Inst. Drug Res., Fac. Med., Hebrew Univ., Jerusalem 91120, Israel; Eng.) -S. Adam 25-104