An expedient approach involving BF3˙OEt2-catalyzed aza-Claisen rearrangement and palladium-catalyzed intramolecular Heck reaction for the synthesis of pyrimidine-fused azocine derivatives is described. The mechanistic interpretation of the plausible mode of cyclization is also described. uracil - aza-Claisen rearrangement - azocine - Heck reaction