Dolby−Weinreb enamine (2), a benzazepine heterocycle, has been a key advanced intermediate in the classical Weinreb synthesis 1 of cephalotaxine (CET, 1), which is the core structure of the structurally unique antileukemia Cephalotaxus alkaloid ester derivatives. 2 Enamine 2 was also synthesized by other groups 3 following the pioneering works by Dolby and Weinreb in this field, via different annulation approaches, as outlined in Figure 1, respectively.